| Submenu or unit | Description | Definition |
| spatial | Units where length is the primary factor |
| ↳ | length |
| ↳ | m | metre (SI base unit) | ≡ 1 m |
| | metric |
| | ↳ | mm | millimetre | ≡ 1/1000 m |
| | | cm | centimetre | ≡ 1/100 m |
| | | km | kilometre | ≡ 1000 m |
| | | Å | ångström | ≡ 1·10-10 m |
| | US/Imp |
| | ↳ | in | inch | ≡ 2.54 cm |
| | | ft | foot | ≡ 12 in |
| | | yd | yard | ≡ 3 ft |
| | | mi | mile | ≡ 1760 yd |
| | other |
| | ↳ | NM | nautical mile | ≡ 1852 m |
| | | AU | astronomical unit | ≡ 149597870691 m |
| | | ly | light year | ≡ 1 y·c = 9460730472580800 m |
| | | pc | parsec | ≡ 360·60·60/2π AU ≈ 3.085677581305729·1016 m |
| area |
| ↳ | m² | square metre (SI unit) | ≡ 1 m² |
| | a | are | ≡ 100 m² |
| | da | decare | ≡ 1000 m² |
| | ha | hectare | ≡ 10000 m² |
| | US/Imp |
| | ↳ | acre | acre | ≡ 4840 yd² |
| | | in² | square inch | ≡ 1 in² |
| | | ft² | square foot | ≡ 1 ft² |
| | | yd² | square yard | ≡ 1 yd² |
| | | mi² | square mile | ≡ 1 mi² |
| speed |
| ↳ | m/s | metre per second (SI unit) | ≡ 1 m/s |
| | km/h | kilometre per hour | ≡ 1 km/h |
| | mph | mile per hour | ≡ 1 mi/h |
| | knot | knot | ≡ 1 NM/h |
| | c | speed of light | ≡ 299792458 m/s |
| volume |
| ↳ | metric |
| | ↳ | m³ | cubic metre (SI unit) | ≡ 1 m³ |
| | | ml | millilitre | ≡ 1/1000 l |
| | | cl | centilitre | ≡ 1/100 l |
| | | dl | decilitre | ≡ 1/10 l |
| | | l | litre | ≡ 1/1000 m³ |
| | U.S. |
| | ↳ | fl.oz | U.S. fluid ounce | ≡ 1/16 pt |
| | | cup | U.S. cup | ≡ 1/2 pt |
| | | pt | U.S. fluid pint | ≡ 1/8 gal |
| | | gal | U.S. fluid gallon | ≡ 231 in³ |
| | | in³ | cubic inch | ≡ 1 in³ |
| | Imp. |
| | ↳ | fl.oz | Imperial fluid ounce | ≡ 1/20 pt |
| | | cup | Imperial cup | ≡ 8 fl.oz |
| | | pt | Imperial pint | ≡ 1/8 gal |
| | | gal | Imperial gallon | ≡ 4.54609 l |
| accel |
| ↳ | m/s² | metre per second squared (SI unit) | ≡ 1 m/s² |
| | in/s² | inch per second squared | ≡ 1 in/s² |
| | ft/s² | foot per second squared | ≡ 1 ft/s² |
| | mi/s² | mile per second squared | ≡ 1 mi/² |
| | g | standard gravity | ≡ 9.80665 m/s² |
| firm | Units where mass is the primary factor |
| ↳ | mass |
| ↳ | kg | kilogram (SI base unit) | ≡ 1 kg |
| | metric |
| | ↳ | g | gram | ≡ 1/1000 kg |
| | | t | tonne / metric ton | ≡ 1000 kg |
| | | u | unified atomic mass unit | ≈ 1.660538782·10-27 kg |
| | US/Imp |
| | ↳ | gr | grain | ≡ 1/7000 lb |
| | | oz | ounce (avoirdupois) | ≡ 1/16 lb |
| | | lb | pound (avoirdupois) | ≡ 0.45359237 kg |
| | | st | stone | ≡ 14 lb |
| | US/Imp |
| | ↳ | ton | short ton | ≡ 2000 lb |
| | | ton | long ton | ≡ 2240 lb |
| force |
| ↳ | N | newton (SI unit) | ≡ 1 kg·m/s² |
| | pdl | poundal | ≡ 1 lb·ft/s² |
| | kgf | kilogram-force | ≡ 1 kg·g |
| | lbf | pound-force | ≡ 1 lb·g |
| energy |
| ↳ | J | joule (SI unit) | ≡ 1 kg·m²/s² |
| | kJ | kilojoule | ≡ 1000 J |
| | cal | calorie (international table) | ≡ 4.1868 J |
| | kcal | kilocalorie | ≡ 1000 cal |
| | Btu | British thermal unit (international table) | ≡ 1055.05585262 J |
| power |
| ↳ | W | watt (SI unit) | ≡ 1 kg·m²/s³ |
| | kW | kilowatt | ≡ 1000 W |
| | MW | megawatt | ≡ 1000000 W |
| | hp | mechanical horsepower | ≡ 745.69987158227022 W |
| pressure |
| ↳ | Pa | pascal (SI unit) | ≡ 1 N/m² |
| | psi | pound per square inch | ≡ 1 lbf/in² |
| | bar | bar | ≡ 100000 Pa |
| | atm | standard atmosphere | ≡ 101325 Pa |
| | mmHg | millimetre of mercury | ≈ 133.322387415 Pa |
| other | Other units |
| ↳ | time |
| ↳ | s | second (SI base unit) | ≡ 1 s |
| | min | minute | ≡ 60 s |
| | h | hour | ≡ 60 min |
| | d | day | ≡ 24 h |
| | y | Julian year | ≡ 365.25 d |
| temp |
| ↳ | K | kelvin (SI base unit) | ≡ 1 K |
| | °C | degree Celsius | T[°C] ≡ T[K] - 273.15 |
| | °F | degree Fahrenheit | T[°F] ≡ T[°C] · 1.8 + 32 |
| | Δ°C | Celsius temperature difference | ≡ 1 K |
| | Δ°F | Fahrenheit temperature difference | ≡ 1/1.8 K |
| chem |
| ↳ | mol | mol (SI base unit) | ≈ 6.02214179·1023 |
| | e | atomic unit of charge | ≈ 1.602176487·10-19 C |
| | eV | electronvolt | ≡ 1 e·V |
| electric |
| ↳ | C | coloumb (SI base unit) | ≡ 1 C |
| | A | ampere (SI unit) | ≡ 1 C/s |
| | V | volt (SI unit) | ≡ 1 W/A = 1 kg·m²/s²·C |
| | Ω | ohm (SI unit) | ≡ 1 V/A = kg·m²/s·C² |
| | more |
| | ↳ | F | farad (SI unit) | ≡ 1 C/V = s²·C²/kg·m² |
| | | Wb | weber (SI unit) | ≡ 1 V·s = kg·m²/s·C |
| | | T | tesla (SI unit) | ≡ 1 Wb/m² = kg/s·C |
| | | H | henry (SI unit) | ≡ 1 Wb/A = kg·m²/C² |