Common unit conversion
length
1 km (km)=0.621 miles (mile)
1 meter (m) = 3.281 feet (ft) = 1.094 yards (yd)
1 centimeter (cm) = 0.394 inches (in)
1 angstrom=10-10 meters (m)
1 mile (mile) = 1.609 km (km)
1 English (fm) = 1.829 (m)
1 foot (ft) = 0.3048 meters (m)
1 inch (in) = 2.54 cm (cm)
1 mile = 1.852 km (km)
1 chain = 66 feet (ft) = 20.1168 meters
1 yards (yd) = 0.9144 meters (m)
1 mil = 0.0254 mm (mm)
1 foot (ft) = 12 inches (in)
1 yard (yd) = 3 feet (ft)
One shot (rad) = 16.5 feet (ft)
1 mile = 5280 feet ft
1 mile = 1.1516 mile (mile)
area
1 square kilometer (km2) = 100 hectares (ha) = 247.1 acres (acre) = 0.386 square miles (mile2)
1 square meter (m2) = 10.764 square feet (ft2)
1 acre (are) = 100 square meters (m2)
1 hectare (ha) = 10,000 square meters (m2) = 2.471 acres (acre)
1 square mile (mile2) = 2.590 square kilometers (km2)
1 acre (acre) = 0.4047 ha (ha) = 4.047 x 10-3 km2 (km2) = 4047 m2 (m2)
1 square foot (ft2) = 0.093 square meters (m2)
1 square inch (in2) = 6.452 square centimeters (cm2)
1 square yard (yd2) = 0.8361 square meters (m2)
volume
1 cubic meter (m3) = 1000 liters (liter) = 35.315 cubic feet (ft3) = 6.29 barrels (bbl)
1 cubic foot (ft3) = 0.0283 cubic meters (m3) = 28.317 liters (liter)
1 thousand cubic feet (mcf) = 28.317 cubic meters (m3)
1 million cubic feet (MMcf) = 28,731,700 cubic meters (m3)
1 billion cubic feet (bcf) = 28.317 million cubic meters (m3)
1 trillion cubic feet (tcf) = 28.317 billion cubic meters (m3)
1 cubic inch (in3)=16.3871 cubic centimeters (cm3)
1 acre feet = 1234 cubic meters (m3)
One barrel (bbl) = 0.159 cubic meters (m3) = 42 gallons (gal)
1 gallon = 3.785 liters (1)
1 US quart (qt) = 0.946 liters (1)
1 US pint (pt) = 0.473 liters (1)
1 US gi (g) = 0.118 liters (1)
1 gallon (gal) = 4.546 liters (1)
quality
1 ton (t) = 1000 kg (kg) = 2205 pounds (lb) = 1.102 short tons (sh.ton) = 0.984 long tons (long ton)
1 kilogram (kg) = 2.205 pounds (lb)
1 short ton (sh.ton) = 0.017 tons (t) = 2000 pounds (lb)
1 long ton = 1.016 tons (t)
1 pound (lb) = 0.454 kg (kg) [equal]
1 ounce (oz) = 28.350 grams (g)
density
1 kg/m3 (kg/m3) = 0.001 g/cm3 (g/cm3) = 0.0624 lb/ft3 (lb/ft3)
1 lb/ft3 (lb/ft3) = 16.02 kg/m3 (kg/m3)
1 lb/in3 (lb/in3) = 27679.9 kg/m3 (kg/m3)
1 lb/gal = 119.826 kg/m3 (kg/m3)
1 lb/gal (lb/gal) = 99.776 kg/m3 (kg/m3)
1 lb/(oil) barrel (lb/bbl) = 2.853 kg/m3 (kg/m3)
1 Specific gravity at the Baume density (B) = 140/15.5°C - 130
Specific gravity of API degree=141.5/15.5°C-131.5
Kinematic viscosity
1 ft2/sec (ft2/s)=9.29030×10-2 m2/s (m2/s)
1 s (St) = 10-4 m2/s (m2/s) = 1 cm2/s (cm2/s)
1 cSt = 10-6 m2/s (m2/s) = 1 mm2/s (mm2/s)
dynamic viscosity
1 poise (P) = 0.1 Pa·s (Pa·s)
1 centipoise (cP) = 10-3 pascal (Pa·s)
1 kgfs/m2 (kgf·s, m2)=9.80665 Pa·s (Pa·s)
1 lbf/s2 (lbf·s/ft2)=47.8803 Pa·s (Pa·s)
force
1 Newton (N)=0.225 pounds force (lbf)=0.102 kilograms force (kgf)
1 kg force (kgf) = 9.81 N (N)
1 lbf (lbf) = 4.45 Newtons (N)
1 dyne = 10-5 Newtons (N)
pressure
1 bar = 105 Pa (Pa)
1 kPa (kPa) = 0.145 lbf/in2 (psi) = 0.0102 kgf/cm2 (kgf/cm2)
=0.0098 atmosphere (atm)
1 lbf/in2 (psi) = 6.895 kPa (kPa) = 0.0703 kgf/cm2 (kg/cm2)
= 0.0689 bar (bar) = 0.068 bar (atm)
1 physical atmosphere (atm) = 101.325 kilopascals (kPa) = 14.696 psi (1.03 bar)
1 project atmospheric pressure = 98.0665 kPa (kPa)
1 mm water column (mmH2O) = 9.80665 Pa (Pa)
1 mmHg = 133.322 Pa
1 Torr = 133.322 Pa (Pa)
1 dyne/cm2 (dyn/cm2) = 0.1 pa (Pa)
temperature
K=5/9 (°F+459.67)
K=°C+273.15
n°F=[(n-32)×5/9]°C
n°C=(5/9·n+32) °F
1°F=5/9°C (temperature difference)
Heat transfer coefficient
1 kcal/(m 2 ·h·°C) [1 kcal/(m 2 ·h·°C)]=1.16279 watts/(m 2 ·Kelvin) [w/(m 2 ·K)]
1 BTU/(ft2·h·°F)[Btu/(ft2·h·°F)]
= 5.67826 watts/(m2•Kelvin)((w/m2·K)〕1 m2·h·°C/kcal (m2·h·°C/kcal)
= 0.86000 m 2 · Kelvin/Watt (m2·K/W)
1 kcal/m2 hour (kcal/m2h) = 1.16279 watts/m2 (w/m2)
Thermal conductivity
1 kcal (mh·°C) [kcal/(m·h·°C)]=1.16279w/(m·Kelvin) [W/(m·K)]
1 BTU/(fth·°F) [But/(ft·h·°F)]=1.7303 W/(m·Kelvin) [W/(m·K)]
Specific heat
1 kcal/(kg·°C)[kcal/(kg·°C)]=1 BTU/(pound·°F)[Btu/(lb·°F)]
= 4186.8 joules/(kg Kelvin) [J/(kg·K)]
Thermal power
1 Joule=0.10204 kg·m=2.778×10-7 kW·h=3.777×10-7 Metric Horsepower Hours=3.723×10-7 Metric Horsepower Hours=2.389×10-4 kcal=9.48×10-4 British Heat unit
1 card (cal) = 4.1868 Joules (J)
1 British thermal unit (Btu) = 1055.06 joules (J)
1 kg of force (kgf·m) = 9.80665 joules (J)
1 foot pound force (ft·lbf)=1.35582 joules (J)
1 metric hp hour (hp · h) = 2.64779 × 106 joules (J)
1 hour (UKHp·h)=2.68452×106 joules
1 kWh (kW·h) = 3.6 × 106 Joules (J)
1 kcal = 4186.75 joules (J)
power
1 kgfm/s (kgf·m/s) = 9.80665W (w)
1 metric hp = 735.499 watts (W)
1 card/second (cal/s) = 4.1868 watts (W)
1 British thermal unit/hour (Btu/h)=0.293071 watts (W)
speed
1 foot/second (ft/s) = 0.3048 meters/second (m/s)
1 mile/h = 0.444704 m/s
Permeability
1 Darcy = 1000 millidarcy
1 square centimeter (cm2) = 9.81 x 107 Darcy
Geothermal gradient
1°F/100 feet = 1.8°C/100 meters (°C/m)
1°C/km = 2.9°F/mile (°F/mile) = 0.055°F/100 feet (°F/ft)
Oil and gas production
1 barrel (bbl) = 0.14 tons (t) (crude oil, global average)
1 t (t) = 7.3 barrels (bbl) (crude oil, global average)
1 barrel/day (bpd) = 50 tons/year (t/a) (crude oil, global average)
1,000 cubic feet per day (Mcfd) = 28.32 cubic meters per day (m3/d) = 103.36 million meters per year (m3/a)
1 million cubic feet per day (MMcfd) = 28,320 cubic meters per day (m3/d) = 10,335,500 cubic meters per year (m3/a)
1 billion cubic feet per day (bcfd) = 0.2832 billion cubic meters per day (m3/d) = 10.336 billion cubic meters per year (m3/a)
1 trillion cubic feet/day (tcfd) = 28.32 billion cubic meters/day (m3/d) = 10.36 trillion cubic meters/year (m3/a)
Gas oil ratio
1 cubic foot/barrel (cuft/bbl) = 0.2067 cubic meter/ton (m3/t)
Heat value
1 barrel of crude oil = 5.8 x 106 Btu
1 cubic meter of moisture = 3.909 x 104 British thermal units (Btu)
1 cubic meter of dry gas = 3.577 x 104 Btu
1 tonne of coal = 2.406 x 107 Btu
1 kilowatt-hour of hydropower = 1.0235 x 104 British heat (Btu)
(The above is the average heating value of the United States in 1990)
(Source: US National Bureau of Standards)
Thermal Equivalent
1 barrel of crude oil = 5,800 cubic feet of natural gas (calculated as average calorific value)
1 kg crude oil = 1.4286 kg standard coal
1 cubic meter natural gas = 1.3300 kg standard coal