| 000 | Generalities | 500 | Pure Sciences |
| 010 | Bibliographies | 510 | Math |
| 020 | Library & Information Science | 520 | Astronomy |
| 030 | General Encyclopedias | 530 | Physics |
| 040 | (Not used) | 540 | Chemistry |
| 050 | General Periodicals | 550 | Earth Science |
| 060 | General Organizations & Museums | 560 | Paleontology |
| 070 | Journalism & Publishing | 570 | Life Sciences |
| 080 | Collections | 580 | Botany |
| 090 | Manuscripts and Rare Books | 590 | Zoology |
| 100 | Philosophy | 600 | Applied Sciences & Technology |
| 110 | Metaphysics | 610 | Medicine |
| 120 | Epistemology | 620 | Engineering |
| 130 | Paranormal Phenomena & Occult | 630 | Agriculture |
| 140 | Specific philosophies | 640 | Home Economics |
| 150 | Psychology | 650 | Management |
| 160 | Logic | 660 | Chemical Technologies |
| 170 | Ethics | 670 | Manufacturing |
| 180 | Ancient, Medieval & Oriental Philosophy | 680 | Application-specific Manufacturing |
| 190 | Modern Western Philosophy | 690 | Building |
| 200 | Religion | 700 | Arts |
| 210 | Natural Religion | 710 | Civic & Landscape Art |
| 220 | Bible | 720 | Architecture |
| 230 | Christian Theology | 730 | Sculpture |
| 240 | Christian Moral Theology | 740 | Drawing |
| 250 | Local Church & Religious Orders | 750 | Painting |
| 260 | Social & Ecclesiastical Theology | 760 | Graphic & Printed Art |
| 270 | History & Geography of Church | 770 | Photography |
| 280 | Christian Denominations & Sects | 780 | Music |
| 290 | Non-Christian & Comparative Religion | 790 | Sports & Recreation |
| 300 | Social Sciences | 800 | Literature |
| 310 | Statistics | 810 | American Literature |
| 320 | Political Science | 820 | English Literature |
| 330 | Economics | 830 | Germanic Literature |
| 340 | Law | 840 | French Literature |
| 350 | Public Administration | 850 | Italian Literature |
| 360 | Social Concerns & Services | 860 | Spanish & Portuguese Literature |
| 370 | Education | 870 | Latin Literature |
| 380 | Trade & Commerce | 880 | Classical Greek Literature |
| 390 | Customs, Etiquette, Folklore | 890 | Literature of Other Languages |
| 400 | Languages | 900 | History & Geography |
| 410 | Linguistics | 910 | Travel & Geography |
| 420 | English Language | 920 | Genealogy & Geography |
| 430 | Germanic & Scandinavian Languages | 930 | Ancient History |
| 440 | French | 940 | European History |
| 450 | Italian | 950 | Asian History |
| 460 | Spanish & Portuguese | 960 | African History |
| 470 | Latin | 970 | North American History |
| 480 | Classical Greek | 980 | South American History |
| 490 | Other Languages | 990 | History of Other Areas |