Dewey Decimal Classification

The Dewey Decimal Classification (DDC) system is a general knowledge organization tool that is continuously revised to keep pace with knowledge. The system was conceived by Melvil Dewey in 1873 and first published in 1876. The DDC is published by OCLC Online Computer Library Center, Inc. OCLC owns all copyright rights in the Dewey Decimal Classification, and licenses the system for a variety of uses. The DDC is the most widely used classification system in the world. Libraries in more than 140 countries use the DDC to organize and provide access to their collections, and DDC numbers are featured in the national bibliographies of more than 60 countries. Libraries of every type apply Dewey numbers on a daily basis and share these numbers through a variety of means (including WorldCat, the OCLC Online Union Catalog). Dewey is also used for other purposes, e.g., as a browsing mechanism for resources on the web.

The Dewey Decimal Classification (DDC) is structured around ten main classes covering the entire world of knowledge; each main class is further structured into ten hierarchical divisions, each having ten divisions of increasing specificity. As a system of library classification the DDC is “arranged by discipline, not subject”, so a topic like clothing is classed based on its disciplinary treatment (psychological influence of clothing at 155.95, customs associated with clothing at 391, and fashion design of clothing at 746.92) within the conceptual framework. The list below presents the ten main classes, hundred divisions, and thousand sections.

  Ten Dewey classes

There’s more! Beyond the decimal point! 

In order to identify all the elements that describe a book’s contents we expand the original number to give more specific 

subject description:

Dewey Classes



A notation is a code commonly used in classification schemes to represent a class, i.e. a subject and its position in the hierarchy, to enable mechanical sorting and filing of subjects. UDC uses Arabic numerals arranged decimally. Every number is thought of as a decimal fraction with the initial decimal point omitted, which determines the filing order. An advantage of decimal notational systems is that they are infinitely extensible, and when new subdivisions are introduced, they need not disturb the existing allocation of numbers. For ease of reading, a UDC notation is usually punctuated after every third digit:


Caption (Class description)


Theoretical problems of elementary particles physics. Theories and models of fundamental interactions


Symmetries of quantum physics


Conservation laws


Translations. Rotations


Reflection in time and space


Space-time symmetries


Internal symmetries




Unified field theories



The list below presents the ten main classes, hundred divisions, and thousand sections:

Class 000 – Computer science, information and general works

 000 Computer science, knowledge and systems
 000 Computer science, information and general works
 001 Knowledge
 002 The book (writing, libraries, and book-related topics)
 003 Systems
 007–009 [Unassigned]
 010 Bibliographies
 010 Bibliography
 011 Bibliographies
 012 Bibliographies of individuals
 013 [Unassigned]
 014 Bibliographies of anonymous and pseudonymous works
 015 Bibliographies of works from specific places
 016 Bibliographies of works on specific subjects
 017 General subject catalogs
 018 Catalogs arranged by author, date, etc.
 019 Dictionary catalogs
 020 Library and information sciences
 021 Library relationships (with archives, information centers, etc.)
 022 Administration of physical plant
 024 [Unassigned]
 026 Libraries for specific subjects
 027 General libraries
 028 Reading and use of other information media
 029 [Unassigned]
 030 Encyclopedias and books of facts
 030 General encyclopedic works
 031 Encyclopedias in American English
 032 Encyclopedias in English
 033 Encyclopedias in other Germanic languages
 034 Encyclopedias in FrenchOccitan, and Catalan
 035 Encyclopedias in ItalianRomanian, and related languages
 036 Encyclopedias in Spanish and Portuguese
 037 Encyclopedias in Slavic languages
 038 Encyclopedias in Scandinavian languages
 039 Encyclopedias in other languages
 040 Unassigned (formerly Biographies)
 050 Magazines, journals and serials
 050 General serial publications
 051 Serials in American English
 052 Serials in English
 053 Serials in other Germanic languages
 054 Serials in French, Occitan, and Catalan
 055 Serials in Italian, Romanian, and related languages
 056 Serials in Spanish and Portuguese
 057 Serials in Slavic languages
 058 Serials in Scandinavian languages
 059 Serials in other languages
 060 Associations, organizations and museums
 060 General organizations and museum science
 061 Organizations in North America
 062 Organizations in British Isles; in England
 063 Organizations in central Europe; in Germany
 064 Organizations in France and Monaco
 065 Organizations in Italy and adjacent islands
 066 Organizations in Iberian peninsula and adjacent islands
 067 Organizations in eastern Europe; in Russia
 068 Organizations in other geographic areas
 069 Museum science
 070 News media, journalism and publishing
 070 News media, journalism, and publishing
 071 Newspapers in North America
 072 Newspapers in British Isles; in England
 073 Newspapers in central Europe; in Germany
 074 Newspapers in France and Monaco
 075 Newspapers in Italy and adjacent islands
 076 Newspapers in Iberian peninsula and adjacent islands
 077 Newspapers in eastern Europe; in Russia
 078 Newspapers in Scandinavia
 079 Newspapers in other geographic areas
 080 Quotations
 080 General collections
 081 Collections in American English
 082 Collections in English
 083 Collections in other Germanic languages
 084 Collections in French, Occitan, Catalan
 085 Collections in Italian, Romanian, and related languages
 086 Collections in Spanish and Portuguese
 087 Collections in Slavic languages
 088 Collections in Scandinavian languages
 089 Collections in other languages
 090 Manuscripts and rare books
 090 Manuscripts and rare books
 091 Manuscripts
 092 Block books
 093 Incunabula
 094 Printed books
 095 Books notable for bindings
 096 Books notable for illustrations
 097 Books notable for ownership or origin
 098 Prohibited works, forgeries, and hoaxes
 099 Books notable for format

Class 100 – Philosophy and psychology

 100 Philosophy
 100 Philosophy and psychology
 101 Theory of philosophy
 102 Miscellany
 103 Dictionaries and encyclopedias
 104 Unassigned
 105 Serial publications
 106 Organizations and management
 107 Education, research, related topics of philosophy
 108 Groups of people
 109 History and collected biography
 110 Metaphysics
 110 Metaphysics
 111 Ontology
 112 No longer used — formerly Methodology
 114 Space
 115 Time
 116 Change
 117 Structure
 118 Force and energy
 119 Number and quantity
 120 Epistemology
 120 Epistemology, causation, and humankind
 121 Epistemology (Theory of knowledge)
 122 Causation
 123 Determinism and indeterminism
 124 Teleology
 125 No longer used — formerly Infinity
 126 The self
 127 The unconscious and the subconscious
 128 Humankind
 129 Origin and destiny of individual souls
 130 Parapsychology and occultism
 130 Parapsychology and occultism
 131 Parapsychological and occult methods for achieving well-being, happiness, success
 132 No longer used — formerly “Mental derangements”
 133 Specific topics in parapsychology and occultism
 134 No longer used — formerly “Mesmerism and Clairvoyance
 135 Dreams and mysteries
 136 No longer used — formerly “Mental characteristics”
 137 Divinatory graphology
 138 Physiognomy
 139 Phrenology
 140 Specific philosophical schools and viewpoints
 141 Idealism and related systems and doctrines
 143 Bergsonism and intuitionism
 144 Humanism and related systems and doctrines
 145 Sensationalism
 146 Naturalism and related systems and doctrines
 147 Pantheism and related systems and doctrines
 148 Dogmatismeclecticism, liberalism, syncretism, and traditionalism
 149 Other philosophical systems and doctrines
 150 Psychology
 150 Psychology
 151 No longer used — formerly “Intellect “
 152 Sensory perceptionmovementemotions, and physiological drives
 153 Conscious mental processes and intelligence
 154 Subconscious and altered states and processes
 157 No longer used — formerly “Emotions
 159 No longer used — formerly “Will”
 160 Philosophical logic
 160 Philosophical logic
 161 Induction
 162 Deduction
 163–164 Not assigned or no longer used
 165 Fallacies and sources of error
 166 Syllogisms
 167 Hypotheses
 168 Argument and persuasion
 169 Analogy
 170 Ethics
 170 Ethics (Moral philosophy)
 171 Ethical systems
 172 Political ethics
 173 Ethics of family relationships
 174 Occupational ethics
 175 Ethics of recreationleisure, public performances, communication
 176 Ethics of sex and reproduction
 177 Ethics of social relations
 178 Ethics of consumption
 179 Other ethical norms
 180 Ancient, medieval, eastern philosophy
 181 Eastern philosophy
 183 Sophistic, Socratic, related Greek philosophies
 189 Medieval Western philosophy
 190 Modern Western and other noneastern philosophy
 191 Philosophy of the United States and Canada
 193 Philosophy of Germany and Austria
 196 Philosophy of Spain and Portugal
 198 Philosophy of Scandinavia and Finland
 199 Philosophy in other geographic areas

Class 200 – Religion

 200 Religion
 200 Religion
 201 Religious mythology, general classes of religion, interreligious relations and attitudes, social theology
 202 Doctrines
 203 Public worship and other practices
 204 Religious experience, life, practice
 205 Religious ethics
 206 Leaders and organization
 207 Missions and religious education
 208 Sources
 209 Sects and reform movements
 210 Philosophy and theory of religion
 210 Philosophy and theory of religion
 211 Concepts of God
 212 Existence, ways of knowing God, attributes of God
 213 Creation
 214 Theodicy
 216 No longer used—formerly Evil
 217 No longer used—formerly Prayer
 218 Humankind
 219 No longer used—formerly Analogies
 220 The Bible
 220 Bible
 221 Old Testament
 222 Historical books of Old Testament
 223 Poetic books of Old Testament
 224 Prophetic books of Old Testament
 225 New Testament
 226 Gospels and Acts
 227 Epistles
 228 Revelation (Apocalypse)
 229 Apocryphapseudepigrapha, and inter-testamental works
 230 Christianity
 230 Christianity
 231 God
 232 Jesus Christ and his family
 233 Humankind
 234 Salvation and grace
 235 Spiritual beings
 236 Eschatology
 237 No longer used—formerly Future state
 238 Creeds, confessions of faith, covenants, and catechisms
 239 Apologetics and polemics
 240 Christian practice and observance
 240 Christian moral and devotional theology
 241 Christian ethics
 242 Devotional literature
 243 Evangelistic writings for individuals and families
 244 No longer used—formerly Religious fiction
 245 No longer used—formerly Hymnology
 246 Use of art in Christianity
 247 Church furnishings and related articles
 249 Christian observances in family life
 250 Christian orders and local church
 250 Local Christian church and Christian religious orders
 251 Preaching (Homiletics)
 252 Texts of sermons
 253 Pastoral office and work (Pastoral theology)
 254 Parish administration
 255 Religious congregations and orders
 256 No longer used — formerly “Religious societies”
 257 No longer used — formerly “Parochial schools, libraries”, etc.
 258 No longer used — formerly “Parochial medicine”
 259 Pastoral care of families, of specific groups of people
 260 Social and ecclesiastical theology
 260 Christian social and ecclesiastical theology
 261 Social theology and interreligious relations and attitudes
 262 Ecclesiology
 263 Days, times, places of religious observance
 264 Public worship
 265 Sacraments, other rites and acts
 266 Missions
 267 Associations for religious work
 269 Spiritual renewal
 270 History of Christianity
 270 History, geographic treatment, biography of Christianity
 271 Religious congregations and orders in church history
 272 Persecutions in church history
 273 Doctrinal controversies and heresies in general church history
 279 History of Christianity in other areas
 280 Denominations and sects of Christian church
 282 Roman Catholic Church
 283 Anglican churches
 284 Protestant denominations of Continental origin and related body
 285 Presbyterian churches, Reformed churches centered in America, Congregational churches
 286 BaptistRestoration MovementAdventist churches
 287 Methodist churches; churches related to Methodism
 288 No longer used — formerly “Unitarian
 289 Other denominations and sects
 290 Other religions
 290 Other religions
 291 No longer used — formerly “Comparative religion”
 292 Classical religion (Greek and Roman religion)
 295 Zoroastrianism (Mazdaism, Parseeism)
 296 Judaism
 297 IslamBábism and Baháʼí Faith
 298 No longer used — formerly “Mormonism
 299 Religions not provided for elsewhere

Class 300 – Social sciences

 300 Social sciences, sociology and anthropology
 300 Social sciences
 301 Sociology and anthropology
 303 Social processes
 304 Factors affecting social behavior
 306 Culture and institutions
 307 Communities
 308 No longer used — formerly “Polygraphy
 309 No longer used — formerly “History of sociology
 310 Statistics
 310 Collections of general statistics
 311 No longer used — formerly “Theory and methods”
 312 No longer used — formerly “Population”
 313 No longer used — formerly “Special topics”
 314 General statistics of Europe
 315 General statistics of Asia
 316 General statistics of Africa
 317 General statistics of North America
 318 General statistics of South America
 319 General statistics of Australasia, Pacific Ocean islands, Atlantic Ocean islands, Arctic islands, Antarctica
 320 Political science (Politics and government)
 321 Systems of governments and states
 322 Relation of state to organized groups and their members
 323 Civil and political rights
 324 The political process
 325 International migration and colonization
 326 Slavery and emancipation
 328 The legislative process
 329 Not assigned or no longer used
 330 Economics
 330 Economics
 331 Labor economics
 333 Economics of land and energy
 334 Cooperatives
 335 Socialism and related systems
 336 Public finance
 338 Production
 339 Macroeconomics and related topics
 340 Law
 340 Law
 341 Law of nations
 343 Military, defense, public property, public finance, tax, commerce (trade), industrial law
 344 Labor, social service, education, cultural law
 345 Criminal law
 346 Private law
 347 Procedure and courts
 348 Lawsregulationscases
 349 Law of specific jurisdictions, areas, socioeconomic regions, regional intergovernmental organizations
 350 Public administration and military science
 351 Public administration
 352 General considerations of public administration
 353 Specific fields of public administration
 354 Public administration of economy and environment
 356 Foot forces and warfare
 357 Mounted forces and warfare
 358 Air and other specialized forces and warfare; engineering and related services
 359 Sea forces and warfare
 360 Social problems and social services
 360 Social problems and services; associations
 361 Social problems and services
 362 Social problems of and services to groups of people
 363 Other social problems and services
 364 Criminology
 365 Penal and related institutions
 366 Secret associations and societies
 367 General clubs
 368 Insurance
 369 Associations
 370 Education
 370 Education
 371 Schools and their activities, special education
 372 Primary education (elementary education)
 374 Adult education
 375 Curricula
 376 No longer used — formerly “Education of women
 377 No longer used — formerly “Ethical education”
 378 Higher education (Tertiary education)
 379 Public policy issues in education
 380 Commerce, communications transportation
 381 Commerce (Trade)
 382 International commerce (Foreign trade)
 384 Communications
 386 Inland waterway and ferry transportation
 388 Transportation
 389 Metrology and standardization
 390 Customsetiquette and folklore
 390 Customs, etiquette, folklore
 392 Customs of life cycle and domestic life
 393 Death customs
 394 General customs
 395 Etiquette (Manners)
 396 No longer used — formerly “Women’s position and treatment”
 397 No longer used — formerly “outcast studies”
 398 Folklore
 399 Customs of war and diplomacy

Class 400 – Language

 400 Language
 400 Language
 401 Philosophy and theory, international languages
 402 Miscellany
 403 Dictionariesencyclopedias, concordances
 404 Special topics of language
 405 Serial publications
 406 Organizations and management
 407 Education, research, related topics
 408 Groups of people
 409 Geographic treatment and biography
 410 Linguistics
 410 Linguistics
 411 Writing systems of standard forms of languages
 412 Etymology of standard forms of languages
 413 Dictionaries of standard forms of languages
 414 Phonology and phonetics of standard forms of languages
 415 Grammar of standard forms of languages
 416 No longer used — formerly “Prosody
 418 Standard usage (Prescriptive linguistics)
 419 Sign languages
 420 English and Old English languages
 420 English and Old English (Anglo-Saxon)
 421 Writing systemphonology, phonetics of standard English
 422 Etymology of standard English
 423 Dictionaries of standard English
 424 No longer used — formerly “English thesauruses
 425 Grammar of standard English
 426 No longer used — formerly “English prosodies
 427 Historical and geographical variations, modern nongeographic variations of English
 428 Standard English usage (Prescriptive linguistics)
 429 Old English (Anglo-Saxon)
 430 German and related languages
 430 German and related languages
 431 Writing systemsphonology, phonetics of standard German
 432 Etymology of standard German
 433 Dictionaries of standard German
 434 Not assigned or no longer used
 435 Grammar of standard German
 436 Not assigned or no longer used
 437 Historical and geographic variations, modern nongeographic variations of German
 438 Standard German usage (Prescriptive linguistics)
 439 Other Germanic languages
 440 French and related languages
 440 French and related Romance languages
 441 Writing systemsphonology, phonetics of standard French
 442 Etymology of standard French
 443 Dictionaries of standard French
 444 Not assigned or no longer used
 445 Grammar of standard French
 446 Not assigned or no longer used
 447 Historical and geographic variations, modern nongeographic variations of French
 448 Standard French usage (Prescriptive linguistics)
 449 Occitan CatalanFranco-Provençal
 450 ItalianRomanian and related languages
 450 Italian, Dalmatian, Romanian, RhaetianSardinianCorsican
 451 Writing systems, phonology, phonetics of standard Italian
 452 Etymology of standard Italian
 453 Dictionaries of standard Italian
 454 Not assigned or no longer used
 455 Grammar of standard Italian
 456 Not assigned or no longer used
 457 Historical and geographic variations, modern nongeographic variations of Italian
 458 Standard Italian usage (Prescriptive linguistics)
 459 Romanian, Rhaetian, Sardinian, Corsican
 460 SpanishPortuguese, Galician
 460 Spanish, Portuguese, Galician
 461 Writing systemsphonology, phonetics of standard Spanish
 462 Etymology of standard Spanish
 463 Dictionaries of standard Spanish
 464 Not assigned or no longer used
 465 Grammar of standard Spanish
 466 Not assigned or no longer used
 467 Historical and geographic variations, modern nongeographic variations of Spanish
 468 Standard Spanish usage (Prescriptive linguistics)
 469 Portuguese
 470 Latin and Italic languages
 470 Latin and related Italic languages
 471 Writing systems, phonology, phonetics of classical Latin
 472 Etymology of classical Latin
 473 Dictionaries of classical Latin
 474 Not assigned or no longer used
 475 Grammar of classical Latin
 476 Not assigned or no longer used
 477 Old, postclassical, Vulgar Latin
 478 Classical Latin usage (Prescriptive linguistics)
 479 Other Italic languages
 480 Classical and modern Greek languages
 480 Classical Greek and related Hellenic languages
 481 Writing systems, phonology, phonetics of classical Greek
 482 Etymology of classical Greek
 483 Dictionaries of classical Greek
 484 Not assigned or no longer used
 485 Grammar of classical Greek
 486 Not assigned or no longer used
 488 Classical Greek usage (Prescriptive linguistics)
 489 Other Hellenic languages
 490 Other languages
 490 Other languages
 491 East Indo-European and Celtic languages
 493 Non-Semitic Afro-Asiatic languages
 494 AlticUralic, Hyperborean, Dravidian languages, miscellaneous languages of south Asia
 495 Languages of East and Southeast Asia
 499 Non-Austronesian languages of Oceania, Austronesian languages, miscellaneous languages

Class 500 – Science

 500 Science
 500 Natural sciences and mathematics
 501 Philosophy and theory
 502 Miscellany
 503 Dictionaries, encyclopediasconcordances
 504 Not assigned or no longer used
 505 Serial publications
 506 Organizations and management
 507 Education, research, related topics
 508 Natural history
 509 Historygeographic treatment, biography
 510 Mathematics
 510 Mathematics
 511 General principles of mathematics
 512 Algebra
 513 Arithmetic
 514 Topology
 515 Analysis
 516 Geometry
 517 Not assigned or no longer used
 520 Astronomy
 520 Astronomy and allied sciences
 522 Techniques, procedures, apparatus, equipment, materials
 523 Specific celestial bodies and phenomena
 524 Not assigned or no longer used
 525 Earth (Astronomical geography)
 526 Mathematical geography
 528 Ephemerides
 529 Chronology
 530 Physics
 530 Physics
 531 Classical mechanics
 532 Fluid mechanics
 533 Pneumatics (Gas mechanics)
 534 Sound and related vibrations
 535 Light and related radiation
 536 Heat
 537 Electricity and electronics
 538 Magnetism
 539 Modern physics
 540 Chemistry
 540 Chemistry and allied sciences
 542 Techniques, procedures, apparatus, equipment, materials
 544 No longer used — formerly “Qualitative analysis
 545 No longer used — formerly “Quantitative analysis
 548 Crystallography
 549 Mineralogy
 550 Earth sciences and geology
 550 Earth sciences
 552 Petrology
 554 Earth sciences of Europe
 555 Earth sciences of Asia
 556 Earth sciences of Africa
 557 Earth sciences of North America
 558 Earth sciences of South America
 559 Earth sciences of Australasia, Pacific Ocean islands, Atlantic Ocean islands, Arctic islands, Antarctica, extraterrestrial worlds
 560 Fossils and prehistoric life
 560 Paleontology
 561 Paleobotany, fossil microorganisms
 562 Fossil invertebrates
 563 Miscellaneous fossil marine and seashore invertebrates
 564 Fossil Mollusca and Molluscoidea
 565 Fossil Arthropoda
 566 Fossil Chordata
 567 Fossil cold-blooded vertebrates
 568 Fossil Aves (birds)
 569 Fossil Mammalia
 570 Biology
 570 Biology
 571 Physiology and related subjects
 572 Biochemistry
 573 Specific physiological systems in animals, regional histology and physiology in animals
 574 Not assigned or no longer used
 575 Specific parts of and physiological systems in plants
 576 Genetics and evolution
 577 Ecology
 578 Natural history of organisms and related subjects
 579 Natural history of microorganismsfungialgae
 580 Plants
 580 Plants
 581 Specific topics in natural history of plants
 582 Plants noted for specific vegetative characteristics and flowers
 583 Magnoliopsida (Dicotyledones)
 584 Liliopsida (Monocotyledones)
 585 Pinophyta (Gymnosperms)
 586 Cryptogamia (Seedless plants)
 587 Pteridophyta
 588 Bryophyta
 589 No longer used—formerly Forestry
 590 Animals (Zoology)
 590 Animals
 591 Specific topics in natural history of animals
 592 Invertebrates
 593 Miscellaneous marine and seashore invertebrates
 594 Mollusca and Molluscoidea
 595 Arthropoda
 596 Chordata
 597 Cold-blooded vertebrates
 598 Aves (Birds)
 599 Mammalia (Mammals)

Class 600 – Technology

 600 Technology
 600 Technology (Applied sciences)
 601 Philosophy and theory
 602 Miscellany
 603 Dictionaries, encyclopedias, concordances
 604 Technical drawing, hazardous materials technology; groups of people
 605 Serial publications
 606 Organizations
 607 Education, research, related topics
 608 Patents
 609 History, geographic treatment, biography
 610 Medicine and health
 610 Medicine and health
 613 Personal health and safety
 614 Forensic medicine; incidence of injuries, wounds, disease; public preventive medicine
 615 Pharmacology and therapeutics
 616 Diseases
 617 Surgery, regional medicine, dentistryophthalmologyotologyaudiology
 618 Gynecology, obstetrics, pediatrics, geriatrics
 619 No longer used—formerly Experimental medicine
 620 Engineering
 620 Engineering and applied operations
 621 Applied physics
 622 Mining and related operations
 625 Engineering of railroadsroads
 626 Not assigned or no longer used
 628 Sanitary engineering
 629 Other branches of engineering
 630 Agriculture
 630 Agriculture and related technologies
 631 Specific techniques; apparatus, equipment, materials
 632 Plant injuries, diseasespests
 633 Field and plantation crops
 634 Orchardsfruitsforestry
 635 Garden crops (Horticulture)
 637 Processing dairy and related products
 638 Insect culture
 639 Huntingfishingconservation, related technologies
 640 Home and family management
 640 Home and family management
 641 Food and drink
 642 Meals and table service
 643 Housing and household equipment
 644 Household utilities
 646 Sewingclothing, management of personal and family life
 647 Management of public households (Institutional housekeeping)
 648 Housekeeping
 649 Child rearinghome care of people with disabilities and illnesses
 650 Management and public relations
 650 Management and auxiliary services
 651 Office services
 652 Processes of written communication
 653 Shorthand
 654–656 Not assigned or no longer used
 657 Accounting
 658 General management
 660 Chemical engineering and related technologies
 661 Technology of industrial chemicals
 662 Technology of explosivesfuels, related products
 663 Beverage technology
 664 Food technology
 665 Technology of industrial oilsfatswaxes, gases
 666 Ceramic and allied technologies
 667 Cleaningcolor, coating, related technologies
 668 Technology of other organic products
 669 Metallurgy
 670 Manufacturing
 670 Manufacturing
 671 Metalworking processes and primary metal products
 672 Ironsteel, other iron alloys
 673 Nonferrous metals
 674 Lumber processing, wood products, cork
 675 Leather and fur processing
 677 Textiles
 678 Elastomers and elastomer products
 679 Other products of specific kinds of materials
 680 Manufacture for specific uses
 680 Manufacture of products for specific uses
 681 Precision instruments and other devices
 682 Small forge work (Blacksmithing)
 684 Furnishings and home workshops
 685 Leather and fur goods, and related products
 686 Printing and related activities
 687 Clothing and accessories
 688 Other final products, and packaging technology
 689 Not assigned or no longer used
 690 Construction of buildings
 690 Construction of buildings
 691 Building materials
 692 Auxiliary construction practices
 693 Construction in specific types of materials and for specific purposes
 695 Roof covering
 696 Utilities
 697 Heatingventilatingair-conditioning engineering
 698 Detail finishing
 699 Not assigned or no longer used


Class 700 – Arts and recreation

 700 Arts
 700 The Arts
 701 Philosophy and theory of fine and decorative arts
 702 Miscellany of fine and decorative arts
 703 Dictionaries, encyclopedias, concordances of fine and decorative arts
 704 Special topics in fine and decorative arts
 705 Serial publications of fine and decorative arts
 706 Organizations and management of fine and decorative arts
 707 Education, research, related topics of fine and decorative arts
 708 Galleries, museums, private collections of fine and decorative arts
 709 History, geographic treatment, biography
 710 Area planning and landscape architecture
 710 Area planning and landscape architecture
 711 Area planning (Civic art)
 712 Landscape architecture (Landscape design)
 713 Landscape architecture of trafficways
 714 Water features in landscape architecture
 715 Woody plants in landscape architecture
 716 Herbaceous plants in landscape architecture
 717 Structures in landscape architecture
 718 Landscape design of cemeteries
 719 Natural landscapes
 720 Architecture
 720 Architecture
 721 Architectural materials and structural elements
 722 Architecture from earliest times to c. 300
 723 Architecture from c. 300 to 1399
 724 Architecture from 1400
 725 Public structures
 727 Buildings for educational and research purposes
 729 Design and decoration of structures and accessories
 730 Sculpture, ceramics and metalwork
 730 Sculpture and related arts
 731 Processes, forms, subjects of sculpture
 732 Sculpture from earliest times to c. 500, sculpture of non-literate peoples
 734 Sculpture from ca 500 to 1399
 735 Sculpture from 1400
 736 Carving and carvings
 737 Numismatics and sigillography
 738 Ceramic arts
 739 Art metalwork
 740 Graphic arts and decorative arts
 740 Graphic arts
 741 Drawing and drawings
 742 Perspective in drawing
 743 Drawing and drawings by subject
 744 Not assigned or no longer used
 745 Decorative arts
 746 Textile arts
 748 Glass
 749 Furniture and accessories
 750 Painting
 750 Painting and paintings
 751 Techniques, procedures, apparatus, equipment, materials, forms
 752 Color
 754 Genre paintings
 755 Religion
 756 Not assigned or no longer used
 757 Human figures
 758 Nature, architectural subjects and cityscapes, other specific subjects
 759 History, geographic treatment, biography
 760 Printmaking and prints
 760 Printmaking and prints
 761 Relief processes (Block printing)
 762 Not assigned or no longer used
 763 Lithographic processes (Planographic processes)
 765 Metal engraving
 766 Mezzotinting, aquatinting, and related processes
 767 Etching and drypoint
 768 Not assigned or no longer used
 769 Prints
 770 Photography, computer art, film, video
 770 Photography, computer art, cinematography, videography
 771 Techniques, procedures, apparatus, equipment, materials
 772 Metallic salt processes
 773 Pigment processes of printing
 774 No longer used—formerly Holography
 775 No longer used—formerly Digital photography
 776 Computer art (Digital art)
 777 Cinematography and Videography
 778 Specific fields and special kinds of photography
 780 Music
 780 Music
 782 Vocal music
 783 Music for single voices
 784 Instruments and Instrumental ensembles and their music
 785 Ensembles with only one instrument per part
 786 Keyboard, mechanical, electrophonic, percussion instruments
 787 Stringed instruments (Chordophones)
 788 Wind instruments (Aerophones)
 789 Unassigned or no longer used
 790 Outline of sports, games and entertainment
 790 Recreational and performing arts
 791 Public performances
 792 Stage presentations
 793 Indoor games and amusements
 794 Indoor games of skill
 795 Games of chance
 796 Athletic and outdoor sports and games
 797 Aquatic and air sports
 798 Equestrian sports and animal racing
 799 Fishinghuntingshooting

Class 800 – Literature

 800 Literaturerhetoric and criticism
 800 Literature (Belles-lettres) and rhetoric
 801 Philosophy and theory
 802 Miscellany
 803 Dictionaries, encyclopedias, concordances
 804 Not assigned or no longer used
 806 Organizations and management
 807 Education, research, related topics
 808 Rhetoric and collections of literary texts from more than two literatures
 809 History, description, critical appraisal of more than two literatures
 810 American literature in English
 810 American literature in English
 811 American poetry in English
 812 American drama in English
 813 American fiction in English
 814 American essays in English
 815 American speeches in English
 816 American letters in English
 817 American humor and satire in English
 818 American miscellaneous writings in English
 819 No longer used—formerly Puzzle activities
 821 English Poetry
 822 English drama
 823 English fiction
 824 English essays
 825 English speeches
 826 English letters
 827 English humor and satire
 828 English miscellaneous writings
 829 Old English (Anglo-Saxon) literature
 830 German and related literatures
 830 German literature and literatures of related languages
 831 German poetry
 832 German drama
 833 German fiction
 834 German essays
 835 German speeches
 836 German letters
 837 German humor and satire
 838 German miscellaneous writings
 839 Other Germanic literatures
 840 French and related literatures
 840 French literature and literatures of related Romance languages
 841 French poetry
 842 French drama
 843 French fiction
 844 French essays
 845 French speeches
 846 French letters
 847 French humor and satire
 848 French miscellaneous writings
 849 OccitanCatalan, Franco-Provençal literatures
 850 ItalianRomanian and related literatures
 850 Literatures of Italian, Dalmatian, Romanian, Rhaetian, Sardinian, Corsican languages
 851 Italian poetry
 852 Italian drama
 853 Italian fiction
 854 Italian essays
 855 Italian speeches
 856 Italian letters
 857 Italian humor and satire
 858 Italian miscellaneous writings
 859 Literatures of Romanian, Rhaetian, Sardinian, Corsican languages
 860 SpanishPortuguese, Galician literatures
 860 Literatures of Spanish, Portuguese, Galician languages
 861 Spanish poetry
 862 Spanish drama
 863 Spanish fiction
 864 Spanish essays
 865 Spanish speeches
 866 Spanish letters
 867 Spanish humor and satire
 868 Spanish miscellaneous writings
 869 Literatures of Portuguese and Galician languages
 870 Latin and Italic literatures
 870 Latin literature and literatures of related Italic languages
 871 Latin poetry
 872 Latin dramatic poetry and drama
 873 Latin epic poetry and fiction
 874 Latin lyric poetry
 875 Latin speeches
 876 Latin letters
 877 Latin humor and satire
 878 Latin miscellaneous writings
 879 Literatures of other Italic languages
 880 Classical and modern Greek literatures
 880 Classical Greek literature and literatures of related Hellenic languages
 881 Classical Greek poetry
 882 Classical Greek drama
 883 Classical Greek epic poetry and fiction
 884 Classical Greek lyric poetry
 885 Classical Greek speeches
 886 Classical Greek letters
 887 Classical Greek humor and satire
 888 Classical Greek miscellaneous writings
 890 Other literatures
 890 Literatures of other specific languages and language families
 891 East Indo-European and Celtic literatures
 892 Afro-Asiatic literatures
 893 Non-Semitic Afro-Asiatic literatures
 894 Literatures of Altaic, Uralic, Hyperborean, Dravidian languages; literatures of miscellaneous languages of South Asia
 895 Literatures of East and Southeast Asia
 896 African literatures
 897 Literatures of North American native languages
 898 Literatures of South American native languages
 899 Literatures of non-Austronesian languages of Oceania, of Austronesian languages, of miscellaneous languages

Class 900 – History and geography

 900 History
 900 History, geography, and auxiliary disciplines
 901 Philosophy and theory of history
 902 Miscellany of history
 903 Dictionaries, encyclopedias, concordances of history
 904 Collected accounts of events
 905 Serial publications of history
 906 Organizations and management of history
 907 Education, research, related topics of history
 908 History with respect to groups of people
 909 World history
 910 Geography and travel
 910 Geography and travel
 912 Graphic representations of surface of earth and of extraterrestrial worlds
 913 Geography of and travel in the ancient world
 914 Geography of and travel in Europe
 915 Geography of and travel in Asia
 916 Geography of and travel in Africa
 917 Geography of and travel in North America
 918 Geography of and travel in South America
 919 Geography of and travel in Australasia, Pacific Ocean islands, Atlantic Ocean islands, Arctic islands, Antarctica, and on extraterrestrial worlds
 920 Biography and genealogy
 920 Biography, genealogy, insignia
 921–928 This range is reserved as an optional location for biographies, which are shelved alphabetically by subject’s last name.
 929 Genealogy, names, insignia
 930 History of ancient world to c. 499
 931 China to 420
 932 Egypt to 640
 933 Palestine to 70
 934 South Asia to 647
 935 Mesopotamia to 637 and Iranian Plateau to 637
 937 Italian Peninsula to 476 and adjacent territories to 476
 938 Greece to 323
 939 Other parts of ancient world
 940 History of Europe
 941 British Isles
 942 England and Wales
 943 Germany and neighboring central European countries
 944 France and Monaco
 945 Italy, San Marino, Vatican City, Malta
 946 Spain, Andorra, Gibraltar, Portugal
 948 Scandinavia
 949 Other parts of Europe
 950 History of Asia
 950 History of Asia
 951 China and adjacent areas
 952 Japan
 953 Arabian Peninsula and adjacent areas
 954 India and neighboring south Asian countries;
 955 Iran
 956 Middle East (Near East)
 957 Siberia (Asiatic Russia)
 958 Central Asia
 959 Southeast Asia
 960 History of Africa
 961 Tunisia and Libya
 962 EgyptSudan, South Sudan
 963 Ethiopia and Eritrea
 964 Morocco, Ceuta, Melilla Western Sahara, Canary Islands
 965 Algeria
 966 West Africa and offshore islands
 967 Central Africa and offshore islands
 968 Republic of South Africa and neighboring southern African countries
 969 South Indian Ocean islands
 970 History of North America
 971 Canada
 972 MexicoCentral America, West Indies, Bermuda
 973 United States
 974 Northeastern United States (New England and Middle Atlantic states)
 975 Southeastern United States (South Atlantic states)
 976 South central United States
 977 North central United States
 978 Western United States
 979 Great Basin and Pacific Slope region of United States
 980 History of South America
 981 Brazil
 982 Argentina
 983 Chile
 984 Bolivia
 985 Peru
 986 Colombia and Ecuador
 987 Venezuela
 988 Guiana
 989 Paraguay and Uruguay
 990 History of other areas
 990 History of Australasia, Pacific Ocean islands, Atlantic Ocean islands, Arctic islands, Antarctica, extraterrestrial worlds
 991–992 Not assigned or no longer used
 993 New Zealand
 994 Australia
 995 New Guinea and neighboring countries of Melanesia
 996 Polynesia and other Pacific Ocean islands
 997 Atlantic Ocean islands
 998 Arctic islands and Antarctica
 999 Extraterrestrial worlds



This page from our Pratt Library How-To Guide zine illustrates how to read a call number:




Dewey Decimal call numbers are organized as follows:




Before the decimal, books are organized in ascending numerical order from 000-999. These three numbers are the Main Class, organized broadly by the subject of the book.

Books are also organized in ascending order after the decimal; for instance, a book with the call number 700 (no decimal) would precede 700.01, with 700.10 further along the shelf. Numbers after the decimal are subdivisions of the Main Class, organized further by subject and author.

After the number sequence, a letter and number sequence should be first read alphabetically, then numerically in ascending order. So 700.01 A123 would precede 700.01 B231.