| Q | Science |
| Q1 | to | Q380 | Science -- General |
| QA1 | to | QA939 | Mathematics |
| QB1 | to | QB991 | Astronomy, Cosmology |
| QC1 | to | QC718.8 | Physics |
| QC750 | to | QC766 | Magnetism |
| QC770 | to | QC798 | Nuclear Physic, Radioactivity |
| QC801 | to | QC809 | Geophysics |
| QC811 | to | QC849 | Geomagnetism |
| QC851 | to | QC999 | Meteorology, Climatology |
| QD1 | to | QD731 | Chemistry |
| QD901 | to | QD999 | Crystallography |
| QE | Geology |
| QE1 | to | QE350 | General Geology |
| QE351 | to | QE399.2 | Mineralogy |
| QE420 | to | QE499 | Petrology |
| QE500 | to | QE625 | Dynamic and Structural Geology |
| QE521 | to | QE545 | Volcanoes and Earthquakes |
| QE640 | to | QE699 | Stratigraphy |
| QE701 | to | QE996.5 | Paleontology |
| QE761 | to | QE899 | Paleozoology |
| QE901 | to | QE996.5 | Paleobotany |
| QH-QR | Biosciences |
| QH1 | to | QH671 | Natural History, General Biology, Evolution, Ecology |
| QK1 | to | QK977.5 | Botany and Plant Ecology |
| QL1 | to | QL991 | Zoology |
| QR1 | to | QR484 | Microbiology |