How many watt-hours is 1 BTU?

1 BTU (International Table) equals exactly 0.29307107 Wh. This comes from the conversion chain: 1 BTU(IT) = 1055.05585262 joules, and 1 Wh = 3600 joules, so 1055.05585262 / 3600 ≈ 0.29307107 Wh.

How do I convert BTU to watt-hours manually?

Multiply the BTU value by 0.29307107. For example, 1000 BTU × 0.29307107 = 293.07 Wh. To convert watt-hours back to BTU, divide by 0.29307107 (or multiply by 3.41214).

What is the difference between BTU and watt-hour?

Both measure energy. A BTU (British Thermal Unit) is the heat needed to raise 1 pound of water by 1°F. A watt-hour is the energy used by a 1-watt device running for 1 hour (3600 joules). BTU is common in US heating/cooling specs; watt-hour is the standard in electrical and metric contexts.

How do I convert BTU/hr to watts?

BTU/hr is a power unit (energy per hour). Divide by 3.41214 to get watts. For example, 12,000 BTU/hr ÷ 3.41214 ≈ 3517 W (about 3.5 kW). This is a separate conversion from BTU (energy) to Wh.

Why do air conditioners use BTU instead of watts?

US HVAC industry has used BTU ratings for decades because the technology historically came from combustion-based systems (furnaces, boilers) where BTU is a natural unit. The rating denotes the cooling capacity per hour (BTU/hr), not total energy. The convention persists for market consistency even as electrical efficiency is measured in watts.

BTU to Watt Hours Converter

Name: BTU to Watt Hours Converter
Availability: InStock
Author: Nham Vu

Enter a BTU value and get the watt-hour equivalent instantly. Reverse Wh-to-BTU conversion and a reference table included.

Converter

Energy in BTU

Result in watt-hours (Wh)

Reverse: watt-hours to BTU

Energy in watt-hours (Wh)

Result in BTU

Reference Table

BTU Watt-hours (Wh)

1 BTU 0.29307 Wh

5 BTU 1.46536 Wh

10 BTU 2.93071 Wh

50 BTU 14.65355 Wh

100 BTU 29.30711 Wh

250 BTU 73.26777 Wh

500 BTU 146.53554 Wh

1,000 BTU 293.07107 Wh

2,000 BTU 586.14214 Wh

5,000 BTU 1,465.36 Wh

10,000 BTU 2,930.71 Wh

100,000 BTU 29,307.11 Wh

Formula: Wh = BTU × 0.29307107 • BTU = Wh ÷ 0.29307107

Summary

Enter a BTU value and get the watt-hour equivalent instantly. Reverse Wh-to-BTU conversion and a reference table included.

How it works

Enter an energy value in BTU in the top input field.
The watt-hour result appears instantly — no button press needed.
Use the reverse field to convert watt-hours back to BTU.
Click "Copy" next to any result to copy it to your clipboard.
Check the reference table for common BTU-to-Wh values at a glance.

Use cases

Convert HVAC system ratings from BTU to Wh for energy consumption comparisons.
Translate furnace or boiler output from BTU to watt-hours for electrical cost estimates.
Convert food-science calorimeter measurements from BTU to Wh for SI compliance.
Compare air conditioner BTU ratings with kilowatt-hour electricity billing.
Convert BTU values in engineering datasheets to watt-hours for metric system projects.
Estimate battery storage requirements by converting BTU heat load to Wh.

Frequently Asked Questions

Last updated: 2026-07-01 · Reviewed by Nham Vu