energy · International · Modern
SI derived unit of energy and work; 1 J = 1 N·m = 1 kg·m²·s⁻².
Converter
energy · International · Modern
British thermal unit (International Table)
Btu_ITexact
Variant of British thermal unit
- Record
- M508
- Definition quality
- Standardized
- Conversion mode
- multiplicative
- Calculator
- Fully calculable
Definition
British thermal unit (International Table): 1 unit = 1055.05585262 J.
Reference value
One British thermal unit (International Table) is equal to 1,055 joules.
History & use
Specific calculable variant.
Modern use
Current-use record in the project inventory; exact scope should follow the definition and regional/system context shown here.
Did you know?
Variant of British thermal unit.
Sources & evidence
Source tier Tier A · confidence High
Related measurements
calorie
calenergy · International · Modern / historical
The generic calorie is variant-dependent; NIST lists thermochemical, International Table, mean, 15 °C, and 20 °C calories.
variantkilocalorie
kcalenergy · International · Modern / historical
A kilocalorie is 1000 calories, so its joule value depends on the calorie convention.
variantenergy · International · Modern / historical
British thermal unit is variant-dependent; NIST lists IT, thermochemical, mean, and temperature-specific forms.
variantenergy · International · Modern / historical
Non-SI unit accepted for use with the SI; 1 eV = exactly 1.602176634×10⁻¹⁹ J.
kilowatt-hour
kW·henergy · International · Modern
1 kWh = exactly 3.6×10^6 J.
calorie (thermochemical)
cal_thenergy · International · Modern
calorie (thermochemical): 1 unit = 4.184 J.
energy · International · Modern
calorie (International Table): 1 unit = 4.1868 J.