1m = 3.28pie

1pul = 2.54cm = 0.0254m

1pie = 12pul = 10.48cm

1yd = 3pie = 36pul = 91.44cm

1MT = 1,609m

1MM = 1,852m

1Å = 10^-10m = 10^-8cm

1Kg = 2.2Lb

1oz = 28.35g

1Lb = 16oz = 453.6g

1t = 10³Kg = 2,200Lb

1tc = 2000Lb

1tl = 2,240Lb

1@ = 28Lb

1q = 4@ = 112Lb

1uma = 1,67.10²⁴g

1L = 1dm³ = 10cm³ = 10m³

1m³ = 10L = 35.31pie³

1pie³ = 28.32L

1cm³ = 1mL³

1G.I.(Galón Ingles) = 4.546L

1G.USA (Galón USA) = 3.785L

1G.P. (Galón Peruano) = 4L

1segundo = 10dmas = 10² centimas

1minuto(min) = 60segundos(s)

1hora(h) = 60min = 3600s

1día(d) = 24h = 1440min

1año común o civil = 365d

1año comercial = 360d

1año bisiesto = 366d

1lustro = 5años

1década = 10años

1milenio = 10³años

1Hectaria = 104m² = 2.47acres

1acre = 4,046.9m²

1Km² = 100hectareas

1ergo = 1g.cm²/s²

1J = 0.24cal = 1Kg.m²/s² = 10⁷ergio

1cal = 4.184J

1BTU = 252cal

1eV (electron Volt) = 1.6×10^-19J

1CV (cheval au vapeur, caballo de vapor) = 0.9863 HP = 735.49 watt

1atm = 760mmHg(Torr) = 101.3Kpa = 1.013bar

1atm = 1033g/cm² = 14.7 lb/pul² = 10.33mH₂O = 1.013bar