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Energy Unit Conversion Calculator

Convert an energy quantity between kWh, joules, megajoules, International Table Btu and a declared therm convention. Keep energy separate from power.

66 / CONVERT ENERGY

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Starting values are illustrative. Use your own costs, rates and assumptions.

INPUT GROUP 01

Energy quantity

Check the assumptions before acting on a result.

Read the method and example

YOUR CALCULATION

The same energy quantity in five declared units.

Kilowatt-hours (kWh)

100

Joules (J)

360,000,000

Megajoules (MJ)

360

International Table Btu (Btu IT)

341,214.163

Therms at 100,000 Btu IT

3.412

Keep the calculation

Saving is optional and stays on this device. Unsaved edits are not kept when you leave. CSV includes every input and the current results.

Illustrative inputs loaded. Replace them with your own assumptions.

Converting a power rating?

Watts and kilowatts describe a rate of energy transfer. Joules and kilowatt-hours describe an amount of energy. Convert power between W, kW, mechanical hp and BTU/h.

How the energy unit conversion calculator works

The selected unit is converted to joules, then divided by each target unit factor. One kilowatt-hour is 3,600,000 joules; one megajoule is 1,000,000 joules. All outputs describe the same amount of energy.

This tool uses the International Table Btu at 1,055.05585262 joules. Its therm is explicitly 100,000 of those Btu. U.S. therm, EC therm and temperature-specific Btu definitions can differ; match the convention on your source document before comparing values.

Conversion factors are definitions or declared constants rather than fuel characteristics. Converting energy does not calculate a fuel volume, generation efficiency or power draw. No duration is inferred. Results are rounded for display, and the CSV includes the underlying numerical results.

Worked example

100 kWh is 360,000,000 J or 360 MJ. With the declared Btu IT convention it is approximately 341,214.163 Btu IT, or 3.412 therms of 100,000 Btu IT. A zero quantity produces zero in every output.

Sources and assumptions

The source material explains the underlying calculation or pricing structure. Entered prices, costs, schedules and scenario choices are your assumptions; this tool does not obtain supplier quotes or predict actual results.

  • 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.

  • Viscosity Unit Converter

    Relate dynamic and kinematic viscosity using density supplied for the same fluid state.

  • 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.

  • 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.

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