Relation of units

Temperature

°F = °C x 9/5 +32
°C = (°F - 32) x 5/9
°C = K - 273.15

Units of area

1 square inch = 6.452 cm²
1 square foot = 144 square inches = 929.029 cm² = 0.0929 m²
1 square yard = 9 square feet = 8367.26 cm² = 0.8367 m²
1 b = 1 barn = 10^-28 m²

Units of length

1 inch = 2.54 cm
1 foot = 12 inches = 0.3048 m
1 yard = 3 feet = 0.9144 m
1 mile = 1760 yards = 1.6093 km
1 nautic mile = 1.852 km
1 swedish mile = 10 km
1 Å = 1 angstrom = 0.1 nm
1 micron = 0.001 mm
1 mm = 0.03994 inch
1 cm = 10 mm = 0.3957 inch
1 m = 100 cm = 3.2808 feet = 1.0936 yards
1 lightyear = 9.46 Pm
1 pc = 1 parsec = 30.857 Pm
1 AU = 1 astronomic unit = 149.600 Gm

Liquid measures, American (US)

1 fl.oz. = 1 fluid ounce = 0.02957 l
1 pint = 16 fluid ounces = 0.4732 l
1 quart = 2 pints = 0.9464 l
1 gallon = 4 quarts = 3.7853 l
1 ccm = 1 ml = 0.0338 fluid ounces
1 l = 1000 ml = 338.8 fluid ounces = 2.1134 pints = 1.0567 quarts = 0.2642 gallons

Liquid measures, British (Imperial)

1 fluid ounce = 0.0284 l
1 pint = 20 fluid ounces = 0.568 l
1 quart = 2 pints = 1.136 l
1 gallon = 4 quarts = 4.5461 l
1 ccm = 1 ml = 0.0352 fluid ounces
1 l = 1000 ccm = 35.2 fluid ounces = 1.7598 pints = 0.8799 quarts = 0.22 gallons

Avoirdupoids weights

1 grain = 0.0648 g
1 oz = 1 ounce = 437.5008 grains = 28.35 g
1 lb = 1 pound = 16 ounces = 453.59 g = 0.45359 kg
1 g = 15.432 grains = 0.03527 ounces
1 kg = 1000 g = 35.27 ounces = 2.205 pounds

Troy weights

1 grain = 0.0648 g
1 pennyweight = 24 grains = 1.5552 g
1 ounce = 20 pennyweight = 31.1035 g
1 pound = 12 ounces = 373.241 g
1 g = 15.432 grains = 0.03215 ounces
1 kg = 32.15 ounces = 2.679 pounds

Other weights

1 ka = 1 karat = 200mg
1 u = 1.66057·10^-27 kg

Force Units

1 kp = 9.80665 N
1 dyn = 10 µN

Pressure Units

1 Pa = 1 kg/m²
1 atm = 101.325 kPa = 1013.25 hPa = 1.01325 bar = 1013.25 mbar
1 atm = 144.12 PSI = 14,697 psia = 1.03323 at = 1.03323 kp/cm²
1 atm = 101325 kg/m² = 10.1325 kg/cm² = 760 mmHg = 10332.3 mmH₂O
1 torr = 1 mmHg
1 bar = 100 kPa = 14.503774 psi
1 psi = 1 lb_f/in² = 6.894757 kPa

Power Units

1 kpm/s = 9.80665 W
1 hp = 1 horse power = 735.5 W (746 W)
1 kcal/h = 1.163 W

Electrical Charge Units

1 Ah = 3600 Coulombs

Energy Units

1 eV = 1.60219·10^-19 J
1 cal = 4.1868 J
1 kWh = 3.6 MJ
1 kpm = 9.80665 J

Lightechnical units

1 footcandle (lumen/square foot) = 10.764 Lux (lumen/m²)
1 Lux = 0.0929 footcandles