{"success":true,"version":"v1","request":{"tool":"get_calculator_schema","calculator_id":"energy"},"result":{"entity_type":"calculator","id":"energy","calculator_id":"energy","canonical_url":"https://tttkmbb.com/conversion/energy","name":"Energy Converter","title":"Energy Converter – Joules, Calories, kWh, BTU, Therms, Electronvolts and Foot-Pounds","category":"conversion","category_name":"Unit Conversion","tool_name":"convert_energy","featured_mcp_tool":false,"description":"Converts energy between joules (J to GJ), calories (thermochemical cal = 4.184 J, kcal), watt-hours (Wh, kWh, MWh), BTU (International Table, 1055.05585262 J), MMBTU, therm (EC), electronvolts, ergs and foot-pounds.","use_when":"You need an energy amount in another unit, e.g. kWh to MJ, kcal to kJ, BTU to kWh or therms to kWh for utility bills.","do_not_use_when":"You need power (rate of energy, use power), the cost of electricity (use electricity-cost) or calories from macronutrient grams (use calories-from-macros).","inputs":[{"name":"value","label":"Value","type":"number","required":true,"description":"Amount to convert, expressed in from_unit.","example":100},{"name":"from_unit","label":"From unit","type":"enum","required":true,"values":[{"value":"J","label":"Joule (J)","aliases":["joule","joules"]},{"value":"kJ","label":"Kilojoule (kJ)","aliases":["kilojoule","kilojoules"]},{"value":"MJ","label":"Megajoule (MJ)","aliases":["megajoule","megajoules"]},{"value":"GJ","label":"Gigajoule (GJ)","aliases":["gigajoule","gigajoules"]},{"value":"erg","label":"Erg (erg)","aliases":["ergs"]},{"value":"cal","label":"Calorie (thermochemical) (cal)","aliases":["calorie (thermochemical)","calorie-(thermochemical)","calorie(thermochemical)","calorie·(thermochemical)","calorie_(thermochemical)","calorie","calories","thermochemical calorie","thermochemical-calorie","thermochemicalcalorie","thermochemical·calorie","thermochemical_calorie","small calorie","small-calorie","smallcalorie","small·calorie","small_calorie","gram calorie","gram-calorie","gramcalorie","gram·calorie","gram_calorie"]},{"value":"kcal","label":"Kilocalorie (kcal)","aliases":["kilocalorie","kilocalories","food calorie","food-calorie","foodcalorie","food·calorie","food_calorie","food calories","food-calories","foodcalories","food·calories","food_calories","large calorie","large-calorie","largecalorie","large·calorie","large_calorie","dietary calorie","dietary-calorie","dietarycalorie","dietary·calorie","dietary_calorie"]},{"value":"Wh","label":"Watt-hour (Wh)","aliases":["watt-hour","watt hour","watthour","watt·hour","watt_hour","watt-hours","watt hours","watthours","watt·hours","watt_hours"]},{"value":"kWh","label":"Kilowatt-hour (kWh)","aliases":["kilowatt-hour","kilowatt hour","kilowatthour","kilowatt·hour","kilowatt_hour","kilowatt-hours","kilowatt hours","kilowatthours","kilowatt·hours","kilowatt_hours"]},{"value":"MWh","label":"Megawatt-hour (MWh)","aliases":["megawatt-hour","megawatt hour","megawatthour","megawatt·hour","megawatt_hour","megawatt-hours","megawatt hours","megawatthours","megawatt·hours","megawatt_hours"]},{"value":"BTU","label":"British thermal unit (IT) (BTU)","aliases":["british thermal unit (it)","british-thermal-unit-(it)","britishthermalunit(it)","british·thermal·unit·(it)","british_thermal_unit_(it)","british thermal unit","british-thermal-unit","britishthermalunit","british·thermal·unit","british_thermal_unit","british thermal units","british-thermal-units","britishthermalunits","british·thermal·units","british_thermal_units","btu (it)","btu-(it)","btu(it)","btu·(it)","btu_(it)","btus"]},{"value":"MMBTU","label":"Million BTU (MMBTU)","aliases":["million btu","million-btu","millionbtu","million·btu","million_btu","mmbtus","dekatherm","dth"]},{"value":"therm","label":"Therm (EC) (therm)","aliases":["therm (ec)","therm-(ec)","therm(ec)","therm·(ec)","therm_(ec)","therms"]},{"value":"eV","label":"Electronvolt (eV)","aliases":["electronvolt","electron volt","electron-volt","electron·volt","electron_volt","electronvolts","electron volts","electron-volts","electron·volts","electron_volts"]},{"value":"ft_lbf","label":"Foot-pound (ft·lbf)","aliases":["ft-lbf","ft lbf","ftlbf","ft·lbf","foot-pound","foot pound","footpound","foot·pound","foot_pound","foot-pounds","foot pounds","footpounds","foot·pounds","foot_pounds","ft-lb","ft lb","ftlb","ft·lb","ft_lb"]}],"description":"Unit of the input value. Accepted symbols: J, kJ, MJ, GJ, erg, cal, kcal, Wh, kWh, MWh, BTU, MMBTU, therm, eV, ft_lbf; spelled-out names and common abbreviations are accepted too.","example":"kWh"},{"name":"to_unit","label":"To unit","type":"enum","required":true,"values":[{"value":"J","label":"Joule (J)","aliases":["joule","joules"]},{"value":"kJ","label":"Kilojoule (kJ)","aliases":["kilojoule","kilojoules"]},{"value":"MJ","label":"Megajoule (MJ)","aliases":["megajoule","megajoules"]},{"value":"GJ","label":"Gigajoule (GJ)","aliases":["gigajoule","gigajoules"]},{"value":"erg","label":"Erg (erg)","aliases":["ergs"]},{"value":"cal","label":"Calorie (thermochemical) (cal)","aliases":["calorie (thermochemical)","calorie-(thermochemical)","calorie(thermochemical)","calorie·(thermochemical)","calorie_(thermochemical)","calorie","calories","thermochemical calorie","thermochemical-calorie","thermochemicalcalorie","thermochemical·calorie","thermochemical_calorie","small calorie","small-calorie","smallcalorie","small·calorie","small_calorie","gram calorie","gram-calorie","gramcalorie","gram·calorie","gram_calorie"]},{"value":"kcal","label":"Kilocalorie (kcal)","aliases":["kilocalorie","kilocalories","food calorie","food-calorie","foodcalorie","food·calorie","food_calorie","food calories","food-calories","foodcalories","food·calories","food_calories","large calorie","large-calorie","largecalorie","large·calorie","large_calorie","dietary calorie","dietary-calorie","dietarycalorie","dietary·calorie","dietary_calorie"]},{"value":"Wh","label":"Watt-hour (Wh)","aliases":["watt-hour","watt hour","watthour","watt·hour","watt_hour","watt-hours","watt hours","watthours","watt·hours","watt_hours"]},{"value":"kWh","label":"Kilowatt-hour (kWh)","aliases":["kilowatt-hour","kilowatt hour","kilowatthour","kilowatt·hour","kilowatt_hour","kilowatt-hours","kilowatt hours","kilowatthours","kilowatt·hours","kilowatt_hours"]},{"value":"MWh","label":"Megawatt-hour (MWh)","aliases":["megawatt-hour","megawatt hour","megawatthour","megawatt·hour","megawatt_hour","megawatt-hours","megawatt hours","megawatthours","megawatt·hours","megawatt_hours"]},{"value":"BTU","label":"British thermal unit (IT) (BTU)","aliases":["british thermal unit (it)","british-thermal-unit-(it)","britishthermalunit(it)","british·thermal·unit·(it)","british_thermal_unit_(it)","british thermal unit","british-thermal-unit","britishthermalunit","british·thermal·unit","british_thermal_unit","british thermal units","british-thermal-units","britishthermalunits","british·thermal·units","british_thermal_units","btu (it)","btu-(it)","btu(it)","btu·(it)","btu_(it)","btus"]},{"value":"MMBTU","label":"Million BTU (MMBTU)","aliases":["million btu","million-btu","millionbtu","million·btu","million_btu","mmbtus","dekatherm","dth"]},{"value":"therm","label":"Therm (EC) (therm)","aliases":["therm (ec)","therm-(ec)","therm(ec)","therm·(ec)","therm_(ec)","therms"]},{"value":"eV","label":"Electronvolt (eV)","aliases":["electronvolt","electron volt","electron-volt","electron·volt","electron_volt","electronvolts","electron volts","electron-volts","electron·volts","electron_volts"]},{"value":"ft_lbf","label":"Foot-pound (ft·lbf)","aliases":["ft-lbf","ft lbf","ftlbf","ft·lbf","foot-pound","foot pound","footpound","foot·pound","foot_pound","foot-pounds","foot pounds","footpounds","foot·pounds","foot_pounds","ft-lb","ft lb","ftlb","ft·lb","ft_lb"]}],"description":"Unit to convert into (same symbols as from_unit).","example":"MJ"}],"outputs":[{"name":"result","label":"Result","type":"number","decimals":6,"description":"Converted value expressed in to_unit (rounded to 6 decimals; see result_text for very small or very large values)."},{"name":"result_text","label":"Conversion","type":"string","decimals":4,"description":"The conversion as text with 6 significant figures, e.g. \"5 mi = 8.04672 km\"."},{"name":"formula","label":"Unit relation","type":"string","decimals":4,"description":"Relation used, e.g. \"1 mi = 1.609344 km\"."},{"name":"factor","label":"Factor","type":"number","decimals":12,"description":"Multiplier from from_unit to to_unit (result = value × factor); absent for non-linear conversions."},{"name":"conversion_table","label":"Conversion table","type":"object","decimals":12,"description":"The input value expressed in every supported energy unit (6 significant figures), keyed by unit symbol."}],"input_schema":{"type":"object","properties":{"value":{"description":"Amount to convert, expressed in from_unit.","type":"number","examples":[100]},"from_unit":{"description":"Unit of the input value. Accepted symbols: J, kJ, MJ, GJ, erg, cal, kcal, Wh, kWh, MWh, BTU, MMBTU, therm, eV, ft_lbf; spelled-out names and common abbreviations are accepted too.","type":"string","enum":["J","kJ","MJ","GJ","erg","cal","kcal","Wh","kWh","MWh","BTU","MMBTU","therm","eV","ft_lbf"],"examples":["kWh"]},"to_unit":{"description":"Unit to convert into (same symbols as from_unit).","type":"string","enum":["J","kJ","MJ","GJ","erg","cal","kcal","Wh","kWh","MWh","BTU","MMBTU","therm","eV","ft_lbf"],"examples":["MJ"]}},"additionalProperties":false,"required":["value","from_unit","to_unit"]},"output_schema":{"type":"object","properties":{"result":{"description":"Converted value expressed in to_unit (rounded to 6 decimals; see result_text for very small or very large values).","type":"number"},"result_text":{"description":"The conversion as text with 6 significant figures, e.g. \"5 mi = 8.04672 km\".","type":"string"},"formula":{"description":"Relation used, e.g. \"1 mi = 1.609344 km\".","type":"string"},"factor":{"description":"Multiplier from from_unit to to_unit (result = value × factor); absent for non-linear conversions.","type":"number"},"conversion_table":{"description":"The input value expressed in every supported energy unit (6 significant figures), keyed by unit symbol.","type":"object"}}},"formula":"result = value × factor, factor = (1 from_unit in J) / (1 to_unit in J)","method":"cal is the thermochemical calorie (4.184 J) and kcal the food Calorie (4184 J); BTU is the International Table BTU and therm the EC therm (100,000 BTU_IT). The International Steam Table calorie (4.1868 J) and US therm (105,480,400 J) differ by 0.07% and 0.02%.","sources":[{"name":"NIST Special Publication 811 – Guide for the Use of the International System of Units (SI), Appendix B conversion factors","url":"https://www.nist.gov/pml/special-publication-811","type":"standard","retrieved_at":"2026-09-23"},{"name":"BIPM – The International System of Units (SI Brochure, 9th edition)","url":"https://www.bipm.org/en/publications/si-brochure","type":"standard","retrieved_at":"2026-09-23"},{"name":"Wikipedia – Conversion of units","url":"https://en.wikipedia.org/wiki/Conversion_of_units","type":"reference","retrieved_at":"2026-09-23"}],"freshness":{"type":"static","max_age_seconds":null,"note":"Deterministic formula with fixed constants; results never go stale. Inputs supplied by the caller determine the output."},"examples":[{"name":"100 kWh to megajoules","inputs":{"value":100,"from_unit":"kWh","to_unit":"MJ"},"expected":{"result":360,"factor":3.6,"formula":"1 kWh = 3.6 MJ","conversion_table":{"BTU":341214,"kcal":86042.1}},"url":"https://tttkmbb.com/api/v1/calculate/energy?value=100&from_unit=kWh&to_unit=MJ"},{"name":"2000 kcal to kilojoules","inputs":{"value":2000,"from_unit":"kcal","to_unit":"kJ"},"expected":{"result":8368,"factor":4.184,"conversion_table":{"kWh":2.32444,"BTU":7931.34}},"url":"https://tttkmbb.com/api/v1/calculate/energy?value=2000&from_unit=kcal&to_unit=kJ"}],"faq":[{"q":"Is a food Calorie the same as a calorie?","a":"A food Calorie (kcal, 'large calorie') is 1000 thermochemical calories (cal). Use kcal for nutrition labels."},{"q":"Which BTU is used?","a":"The International Table BTU (1055.05585262 J), the definition used by NIST SP 811 and in HVAC ratings. The thermochemical BTU (1054.35 J) is 0.07% smaller."},{"q":"How many kWh in a therm?","a":"29.3071 kWh (1 therm = 100,000 BTU = 105.5056 MJ)."}],"tags":["energy converter","kwh to mj","kcal to kj","btu to kwh","joules to calories","therm"],"related":[{"calculator_id":"power","reason":"Energy per unit time (W, hp, BTU/h)."},{"calculator_id":"electricity-cost","reason":"Cost of a kWh amount at a tariff."},{"calculator_id":"kinetic-energy","reason":"Energy of a moving mass in joules."}],"links":{"html":"https://tttkmbb.com/conversion/energy","markdown":"https://tttkmbb.com/conversion/energy.md","json":"https://tttkmbb.com/conversion/energy.json","api":"https://tttkmbb.com/api/v1/calculate/energy","schema":"https://tttkmbb.com/api/v1/calculators/energy","openapi":"https://tttkmbb.com/openapi.json","mcp":"https://tttkmbb.com/mcp"},"version":"v1","updated_at":"2026-09-23"},"timestamp":"2026-09-23T23:23:49Z"}