How do I convert BTU to kJ?

Use the formula shown above or enter a value to see BTU converted to kJ instantly.

What is the formula for BTU to kJ?

The converter calculates kJ by applying the category-specific conversion factor for Energy.

When should I use BTU vs kJ?

BTU and kJ are both part of the Energy category; pick the unit that matches your measurement context (e.g., scale, region, or industry standard).

Energy Conversion Guide

Convert BTU to kJ

Use the live converter below to translate between British Thermal Unit (BTU) and Kilojoule (kJ). Scroll further for quick examples, formula tips, and related units.

Formula insight: Most unit conversions use a simple multiplication or division by a conversion factor. The calculator shows the exact formula used.

Convert

BTU → kJ

British Thermal Unit

BTU

Kilojoule

1.0551

Rounded result (4 decimals max)

Formula

1 BTU = 1.0551 kJ

Conversion sourcesTap or click to view references

The International System of Units (SI) — NIST Special Publication 330
National Institute of Standards and Technology (NIST). The SI Brochure (SP 330) is the definitive English edition of the BIPM SI tables. NIST’s edition lists the official constants and conversion factors tying inch-pound units to SI, which SwapUnits applies for length, mass, temperature, pressure, volume, and related conversions. See /standards/nist-si-tenfold for the complete decimal multiple/submultiple table. View source · View SI table

Results update as you type. Swap the direction to convert back from kJ to BTU.

Back to main converter

BTU to kJ quick table

Multiply any row by the same factor to scale results. Use the converter above to enter exact values with your own units.

British Thermal Unit (BTU)	Kilojoule (kJ)
0.25 BTU	0.2638 kJ
0.5 BTU	0.5275 kJ
1 BTU	1.0551 kJ
2 BTU	2.1101 kJ
5 BTU	5.2753 kJ
10 BTU	10.5506 kJ
25 BTU	26.3764 kJ
100 BTU	105.5056 kJ

kJ back to BTU

Keep the reciprocal handy when double-checking calculations or undoing a conversion.

Kilojoule (kJ)	British Thermal Unit (BTU)
0.25 kJ	0.237 BTU
0.5 kJ	0.4739 BTU
1 kJ	0.9478 BTU
2 kJ	1.8956 BTU
5 kJ	4.7391 BTU
10 kJ	9.4782 BTU
25 kJ	23.6954 BTU
100 kJ	94.7817 BTU

Explore more energy conversion guide

BTU → J

Convert into Joule without leaving SwapUnits.

BTU → cal

Convert into Calorie without leaving SwapUnits.

BTU → kcal

Convert into Kilocalorie (food) without leaving SwapUnits.

BTU → kWh

Convert into Kilowatt Hour without leaving SwapUnits.

Compare all energy conversion guide

View the full unit roster, charts, and tips for Energy Conversion Guide conversions.

Open category guide