BTU (th) to Calorie (IT) Converter

Energy Converter

27 units available

Decimals:

From

To

251.827171

1 BTU = 251.827171 cal (IT)

Formula:

cal (IT) = BTU × 251.8271711092

With your value: 1 BTU = 251.82717111 cal (IT)

How big is that?

Everyday references on a logarithmic scale, all expressed in btu (th) so you can sanity-check the result.

Heartbeat (1/1.1e+3 your value)0.000948 BTU

Your value1.00 BTU

AA battery charge (9.5× your value)9.48 BTU

Slice of bread (2.7e+2× your value)266 BTU

Daily food intake (8.0e+3× your value)7.97e+3 BTU

Litre of petrol (3.2e+4× your value)3.24e+4 BTU

Other BTU (th) to Calorie (IT) conversions

2 BTU to cal (IT)3 BTU to cal (IT)4 BTU to cal (IT)5 BTU to cal (IT)6 BTU to cal (IT)7 BTU to cal (IT)8 BTU to cal (IT)

BTU (th) to Calorie (IT) Conversion Table

BTU (th) (BTU)	Calorie (IT) (cal (IT))
0.5	125.913586
1	251.827171
2	503.654342
5	1,259.135856
10	2,518.271711
15	3,777.407567
20	5,036.543422
25	6,295.679278
50	12,591.358555
100	25,182.717111
250	62,956.792777
500	125,913.585555
1000	251,827.171109

Calorie (IT) to BTU (th) Conversion Table

Calorie (IT) (cal (IT))	BTU (th) (BTU)
0.5	0.001985
1	0.003971
2	0.007942
5	0.019855
10	0.03971
15	0.059565
20	0.07942
25	0.099274
50	0.198549
100	0.397098
250	0.992744
500	1.985489
1000	3.970977

Where these values come from

Every factor on this page is traced to the document that defines it. See the full provenance dataset or our methodology.

BTU (th) (BTU)

Energy

Exact conversion

The International Table BTU is exactly 1055.055 852 62 J.

Thermochemical and 39 °F BTU definitions differ by up to 0.2 %.

Source: NIST Special Publication 811, Guide for the Use of the International System of Units

National Institute of Standards and Technology (US) · Reviewed 2026-07-01

Calorie (IT) (cal (IT))

Energy

Exact conversion

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

Source: NIST Special Publication 811, Guide for the Use of the International System of Units

National Institute of Standards and Technology (US) · Reviewed 2026-07-01

How to Convert BTU (th) to Calorie (IT)

To convert from BTU (th) (BTU) to Calorie (IT) (cal (IT)), multiply the value by 251.8271711092.

Formula: cal (IT) = BTU × 251.8271711092

Reverse: BTU = cal (IT) × 0.0039709774

Step-by-Step Example

Start with your value in BTU (th). For example: 5 BTU
Multiply by the conversion factor: 5 x 251.8271711092
The result is: 1,259.135856 cal (IT)

About BTU (th)

The btu (th) (BTU) is a unit of energy and work. One btu (th) equals 1054.35 joules. UnitConvertLab converts it against every other energy unit using this exact definition, so results are reproducible to full double precision rather than rounded lookup tables.

Common uses: energy calculations, engineering and science, education.

About Calorie (IT)

The calorie (it) (cal (IT)) is a unit of energy and work. One calorie (it) equals 4.1868 joules. UnitConvertLab converts it against every other energy unit using this exact definition, so results are reproducible to full double precision rather than rounded lookup tables.

Common uses: energy calculations, engineering and science, education.

Frequently Asked Questions

How many Calorie (IT) are in 1 BTU (th)?

There are exactly 251.8271711092 Calorie (IT) in 1 BTU (th). This means the conversion factor from BTU (th) to Calorie (IT) is 251.8271711092.

What is the formula to convert BTU (th) to Calorie (IT)?

The formula to convert BTU (th) to Calorie (IT) is: cal (IT) = BTU × 251.8271711092. For example, to convert 10 BTU (th) to Calorie (IT), you would multiply 10 by 251.8271711092.

What is a BTU (th)?