Energy Unit Conversion
Convert an energy quantity between kWh, joules, megajoules, International Table Btu and a declared therm convention. Keep energy separate from power.
Use energy unit conversion →CALCULATORS BY SUBJECT
Units & measurement calculators
Convert quantities with explicit unit definitions and any required density, pressure or temperature assumptions.
7 free tools. No signup. Methods, examples and source links on every page.
Power Conversion
Convert a known power value between watts (W), kilowatts (kW), mechanical horsepower (hp) and Btu IT per hour. Calculating electrical power from volts and amps is a different task that may also need power factor and phase details.
Use power conversion →Petroleum Barrel Volume
Convert petroleum barrels, U.S. liquid gallons, liters and cubic meters. The barrel is explicitly 42 U.S. liquid gallons, with no temperature correction.
Use petroleum barrel volume →Water Flow Unit Conversion
Convert a steady volumetric flow between liters per minute, liters per second, cubic meters per hour and U.S. gallons per minute.
Use water flow unit conversion →Liquid Mass & Volume
Estimate liquid mass from volume, or volume from mass, using your entered density. See liters, cubic meters, kilograms, tonnes and pounds together.
Use liquid mass & volume →Cooling Efficiency Unit Converter
Convert equivalent steady-state COP, EER and electrical kW per refrigeration ton on the same rating basis.
Use cooling efficiency unit converter →Viscosity Unit Converter
Relate dynamic and kinematic viscosity using density supplied for the same fluid state.
Use viscosity unit converter →Before you use these calculations
Identify the physical quantity before converting. Energy, power, mass, volume and flow are different quantities.
Check the unit convention: U.S. and imperial gallons, mechanical horsepower and other named units can differ.
A mass-to-volume conversion requires a density for the material at the relevant condition. Conversion does not supply that property.
Start with the example, replace the assumptions with your measurements, then change one input to see its effect. Save or export the scenario if you need to keep its basis.
How Case calculators are built and checked →Read practical calculation guides or browse another industry.