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Energy converters calculators

Convert watts, kilowatts, kWh, amps, amp-hours, mAh and BTU.

New to the topic? Read What Is a Kilowatt-Hour (kWh)? Meaning, kW vs kWh and Cost.

Amp Hours to kWhConvert amp hours to kWh with battery voltage: kWh = Ah × V ÷ 1,000. Includes usable energy for lithium and lead-acid and a 12, 24 and 48 V table.Open calculator Amp Hours to Watt HoursConvert amp hours to watt hours with Wh = Ah × V, or watt hours back to amp hours. Tables for 12, 12.8, 24 and 48 V batteries and power banks.Open calculator Amps to kWAmps to kW calculator for single-phase, three-phase and DC circuits. Convert amps to kilowatts with voltage and power factor, plus the 80% breaker load.Open calculator BTU to kWhConvert BTU to kWh, kWh to BTU and therms to kWh using 1 kWh = 3,412.14 BTU. Also turns BTU/h heating and cooling ratings into kW and tons.Open calculator kW to AmpskW to amps calculator for single-phase, three-phase and DC circuits. Convert kilowatts to amps with voltage and power factor, and get the breaker size.Open calculator kW to WattsKilowatt to watt converter: 1 kW = 1,000 W. Convert kW to W, watts to kW, megawatts, horsepower and BTU per hour, with a quick conversion table.Open calculator mAh to kWhConvert mAh to kWh and Wh using battery voltage, or kWh to mAh. Check whether a power bank is under the FAA 100 Wh carry-on limit for flights.Open calculator Watts to kWhConvert watts to kWh: multiply watts by hours and divide by 1,000. Free W to kWh calculator with a conversion table and the cost at the US average price.Open calculator

FAQ

Frequently asked questions

How do I convert watts to kWh?

Multiply watts by hours and divide by 1,000. A 100 W bulb running 10 hours uses 1 kWh.

How many watts are in a kilowatt?

One kilowatt equals 1,000 watts. To convert watts to kilowatts, divide by 1,000.

How do I convert amps to kW?

For single-phase or DC circuits, multiply amps by volts and power factor and divide by 1,000. For three-phase circuits, also multiply by the square root of 3 (about 1.732).

How many BTU are in a kWh?

One kilowatt-hour equals 3,412.14 BTU. A therm of natural gas is 100,000 BTU, or about 29.3 kWh.

How do I convert mAh to kWh?

Multiply mAh by the battery voltage and divide by 1,000 to get watt-hours, then divide by 1,000 again for kWh. A 20,000 mAh power bank at 3.7 V holds 74 Wh, or 0.074 kWh.

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