Free Calculator · Published November 2026
Btu to kWh: Divide 1,055.056 by 3,600,000
One IT British thermal unit is 0.0002930711 kilowatt hours at ten decimals. Btu to kWh divide the NIST joule row for Btu IT, 1.055 056 E+03, by the joule row for a kilowatt hour, 3.6 E+06. One thousand Btu IT are 0.2930711111 kilowatt hours.
The next digit is 1, so the tenth decimal does not round up. This page does not convert Btu per hour.
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Book a DemoHow Btu to kWh Uses the IT Btu
Btu to kWh follow two energy rows on the NIST Guide to the SI, Appendix B.8. The IT British thermal unit multiplies by 1.055 056 and E+03 to reach joules. The kilowatt hour multiplies by 3.6 and E+06 to reach joules. A heating-load estimate stays on the sizing calculator.
All calculations are estimates based on historical information and should be verified by the user.
Important: this is energy, not a bill
All calculations are estimates based on historical information and should be verified by the user. This tool is provided as a free service for planning purposes only and is not a substitute for a professional assessment, a supplier quote, or applicable local code requirements.
What Is Btu to kWh Using?
A nameplate can print Btu and a power bill can print kilowatt hours. Btu to kWh put those two energy units on one line. The result is not a dollar, and it is not the size of a furnace. A load estimate that starts from square feet stays on the BTU calculator.
The IT definition, stated
NIST prints several British thermal units. This page uses only the row labeled British thermal unit IT, 1.055 056 E+03 joules. The next row, British thermal unit th, is 1.054 350 E+03 joules. Mean, 39 °F, 59 °F, and 60 °F rows sit under those. None of them is the factor here.
A kilowatt hour is 3.6 E+06 joules on the same page. Dividing 1,055.056 by 3,600,000 is the whole conversion. The NIST page says factors in boldface are exact. This fetch did not preserve boldface, so the quotient is not called exact. Footnote 9 is printed next to the IT row. The HTML table did not include the footnote sentence, so this page does not invent what that note says.
How many kilowatt hours are in these Btu?
Each row multiplies by the quotient and stops at ten decimals. One hundred thousand Btu IT are 29.3071111111 kilowatt hours. That is energy on the nameplate path. It is not a recovery rate for a water heater.
| Btu IT | Kilowatt hours |
|---|---|
| 1 | 0.0002930711 |
| 1,000 | 0.2930711111 |
| 10,000 | 2.9307111111 |
| 100,000 | 29.3071111111 |
Worked examples
| Case | Btu IT | Kilowatt hours |
|---|---|---|
| 1 Btu IT | 1.0000000000 | 0.0002930711 |
| 1,000 Btu IT | 1000.0000000000 | 0.2930711111 |
| 100,000 Btu IT | 100000.0000000000 | 29.3071111111 |
| 1 kilowatt hour | 3412.1411564884 | 1.0000000000 |
Energy is not Btu per hour
NIST also prints British thermal unit IT per hour into watts as 2.930 711 E-01. That row is power. Btu to kWh do not use it, and they do not turn a furnace input rate into a kilowatt. A water-heater or air-conditioner nameplate that says Btu per hour needs the hour to stay on the note. Dropping the hour and calling the number energy is a different claim.
How should you write btu to kwh?
Write five lines before the number leaves this page. A later visit should not have to guess which Btu was used.
- The entered value, and whether it was Btu IT or kilowatt hours.
- The two joule factors, 1,055.056 and 3,600,000, named as the NIST IT row and the kilowatt-hour row.
- Both results, at ten decimals.
- Which nameplate or bill the energy came from, and that the hour was not dropped.
- A note that the thermochemical Btu and the Btu-per-hour row were not applied, and that the quotient was not called exact.
What stays off this energy
One kilowatt hour divided into Btu IT is 3,600,000 divided by 1,055.056, about 3,412.1412 at four decimals. Three thousand four hundred twelve Btu IT are 0.9999586311 kilowatt hours at ten decimals, not one. The round number people remember is not the quotient. A water-heater nameplate that prints an input rate still has an hour on it. Dropping the hour and running the rate through this energy quotient treats power as if it were a quantity of heat already delivered. Keep the hour on the note. If the customer asks what a year of running would be, that question needs hours of use, which this page does not have. Do not invent a runtime to finish the arithmetic.
The thermochemical row sits one line below the IT row on the NIST table, at 1.054 350 E+03 joules. Using it by accident changes the quotient. If a spec sheet does not say which British thermal unit it means, write IT on your copy only when you used the IT row, and say the sheet was silent. Do not relabel a thermochemical figure as IT to make the decimals match. Footnote 9 is marked on the IT row. The HTML fetch did not include the footnote sentence, so this page does not guess what the note adds.
An HVAC contractor who saves the IT note will not price a kilowatt hour from this page. There is no utility rate here. A heating load is still the HVAC load calculation guide. Water that needs a hardness note, not an energy note, stays on hard water problems.
Frequently Asked Questions
How does the quotient use 1,055.056 and 3,600,000?
Divide the NIST IT British thermal unit, 1.055 056 E+03 joules, by the kilowatt hour, 3.6 E+06 joules. One Btu IT is 0.0002930711 kilowatt hours at ten decimals. The next digit of that quotient is 1, so the tenth decimal does not round up. Boldface was not preserved, so the quotient is not called exact.
Which Btu does btu to kwh use?
The International Table Btu, marked Btu IT on the NIST page, 1.055 056 E+03 joules. The thermochemical Btu on the next row is 1.054 350 E+03. This page does not use that row.
Does btu to kwh convert Btu per hour to kilowatts?
No. Btu IT per hour into watts is a different NIST row, 2.930 711 E-01. That is power. This page converts energy. A sizing calculator that estimates a heating load is also a different page.
How many Btu IT are in one kilowatt hour?
3,600,000 divided by 1,055.056 is about 3,412.1412 Btu IT at four decimals. That reverse figure is the division. It is not a second factor printed on the NIST page, and 3,412 alone is not exact.
Save the IT Btu Next to the Kilowatt Hour
The nameplate energy and the NIST joule rows belong on the customer record. The rate does not.
Get a Free DemoAll calculations are estimates based on historical information and should be verified by the user. This tool is provided as a free service for planning purposes only and is not a substitute for a professional assessment, a supplier quote, or applicable local code requirements.