How many kcal is 1,000 kJ?

239.005736138 kcal, the twelve-significant-digit display of 1,000 / 4.184 using the thermochemical convention. The division scales straight up and down: 100 kJ is 23.9005736138 kcal, 250 kJ is 59.7514340344 kcal, 500 kJ is 119.502868069 kcal and 2,000 kJ is 478.011472275 kcal. Type any of them into the From box and the headline updates as you type, to twelve significant digits.

What is the formula for kJ to kcal?

For thermochemical kilocalories, kcal = kJ / 4.184. Multiplying by the rounded reciprocal 0.239005736138 only approximates that division and can change final rounding. In reverse, kJ = kcal × 4.184: 100 kcal is exactly 418.4 kJ, 250 kcal exactly 1,046 kJ and 2,000 kcal exactly 8,368 kJ. Exact terminating factors can still produce long outputs that round to twelve significant digits. Swap units reverses the pair and keeps the typed scalar.

Why does a food label print two energy numbers?

A source can show one energy quantity in kilojoules and kilocalories. A food Calorie commonly means a kilocalorie, but labels, calorie conventions and calculation rules vary. For an explicitly supplied thermochemical kcal quantity, 1 kcal is exactly 4.184 kJ. The converter uses that stated definition; it cannot determine a label’s jurisdiction, rounding or method for deriving its energy figures.

Why do the kJ and kcal on my pack not divide out to exactly 4.184?

Separately rounded values or independently calculated energy figures can yield a different ratio. For example, 670 kJ converts here to 160.133843212 thermochemical kcal; a printed pair 670 kJ and 160 kcal therefore need not retain an exact 4.184 ratio. If a supplied factor table uses 17 kJ/g alongside 4 kcal/g, its ratio is 4.25; 37 kJ/g alongside 9 kcal/g gives about 4.11. Those are arithmetic examples, not a finding about your pack or proof that it is correct. This converter cannot identify the source’s factors, rounding rules or calorie convention.

Is a kcal the same as a Calorie with a capital C?

Food Calorie commonly means a kilocalorie, 1,000 small calories under the same definition. Check the source’s convention. Here the Calorie (cal) is thermochemical, exactly 4.184 J, and Kilocalorie (kcal) exactly 4,184 J. Thus a stated 250 thermochemical kcal is exactly 1,046 kJ, and 1,000 kJ displays as 239,005.736138 cal or 239.005736138 kcal. Choose the explicit unit your source documents rather than relying on capitalization alone.

Which calorie does food energy use, 4.184 or 4.1868?

This converter uses the thermochemical calorie of exactly 4.184 J and its kilocalorie of exactly 4,184 J. The International Table calorie is exactly 4.1868 J, about 0.0669% larger. With the thermochemical definition 2,000 kJ displays as 478.011472275 kcal; divided by 4.1868 it gives 477.691793255 IT kcal, about 0.32 kcal less. IT kcal is absent from the menu. The tool cannot establish which definition or calculation rules an external food-energy source uses.

Is dividing by 4.2 close enough?

Dividing by 4.2 is about 0.38% below the thermochemical conversion: 1,000 / 4.2 displays as 238.095238095 kcal, while 1,000 / 4.184 displays as 239.005736138 kcal. Multiplying by 0.24 is about 0.42% high and gives 240 kcal for the same 1,000 kJ. These are approximations; choose the precision needed for the stated calculation. The displayed values from division by 4.184 still round to twelve significant digits.

What else does this page show, and why does it open on kJ and kcal?

The other common energy units appear below, using thermochemical cal/kcal and IT BTU. For 1,000 kJ, outputs include 277.777777778 Wh, 0.277777777778 kWh and 947.817120313 BTU; Show 1 more adds electronvolts. This focused page opens on Kilojoule and Kilocalorie, while preserving the main converter’s saved unit pair. When storage is usable, a saved value and uncommon-unit preference can travel between pages. Its suffix must still match From. Valid deliberate scalar edits can save those fields after a short delay; invalid or incomplete drafts preserve the saved record. Unusable or conflicting records remain until you use Forget saved settings, which keeps the current conversion on screen. Copy result copies the displayed headline without digit-grouping commas; each visible conversion row has its own Copy button. Displayed and copied values round to twelve significant digits. If native copying fails, a complete selectable summary identifies the input, selected pair and conventions and includes every unit in the category, including uncommon units. Your input and converted values are calculated in the browser and are not uploaded by the converter. The definitions arrive with the page, so conversion needs no external data lookup and keeps working offline after the page has loaded. The core conversion needs no account.

kJ to kcal Converter

One thermochemical kilocalorie is exactly 4.184 kilojoules, so kilojoules to kilocalories is a single division: kcal = kJ / 4.184. That makes 1,000 kJ 239.005736138 kcal, 100 kJ 23.9005736138 kcal and 4.184 kJ exactly 1 kcal, and it runs the other way as kJ = kcal × 4.184, so 250 kcal is exactly 1,046 kJ and 2,000 kcal is exactly 8,368 kJ. The 4.184 is a definition rather than a measurement: the thermochemical calorie was fixed at exactly 4.184 joules, and the kilocalorie here is exactly 1,000 of those calories; check an external source’s convention rather than assuming its labeling method. This page opens the converter with kilojoules in the From box and kilocalories in the To box, whatever pair you converted last, shows the answer to twelve significant digits, and lists the same energy in joules, calories, watt hours, kilowatt hours and IT British thermal units under it. It changes units only: it knows nothing about what is in the pack and gives no dietary guidance.

From

To0.239005736138

Category: Energy

Base unit: joule

Uncommon units: Show 1 more

BTU uses the International Table definition (1,055.05585262 J); cal and kcal are thermochemical (4.184 J per cal). Wh and kWh are energy, not power in W or kW.

Results round to 12 significant digits using the listed unit definitions. Input must have a finite numeric magnitude and at most 512 significant digits. Type a single decimal or scientific number; a matching From unit suffix is accepted. Commas and grouped spaces separate thousands; decimal commas, fractions and compound measurements are refused.

1 kJ in every energy unit

JouleJ
1,000
Caloriecal
239.005736138
Kilocaloriekcal
0.239005736138
Watt hourWh
0.277777777778
Kilowatt hourkWh
0.000277777777778
British thermal unitBTU
0.947817120313

Selectable complete conversion

Unit Converter — Energy
Input: 1 (Kilojoule, kJ)
Result: 0.239005736138 kcal (Kilocalorie)
Displayed values round to 12 significant digits.
BTU uses the International Table definition (1,055.05585262 J); cal and kcal are thermochemical (4.184 J per cal). Wh and kWh are energy, not power in W or kW.
All other units:
Joule (J): 1000
Calorie (cal): 239.005736138
Kilocalorie (kcal): 0.239005736138
Watt hour (Wh): 0.277777777778
Kilowatt hour (kWh): 0.000277777777778
British thermal unit (BTU): 0.947817120313
Electronvolt (eV): 6.24150907446e21

Common questions

How many kcal is 1,000 kJ?: 239.005736138 kcal, the twelve-significant-digit display of 1,000 / 4.184 using the thermochemical convention. The division scales straight up and down: 100 kJ is 23.9005736138 kcal, 250 kJ is 59.7514340344 kcal, 500 kJ is 119.502868069 kcal and 2,000 kJ is 478.011472275 kcal. Type any of them into the From box and the headline updates as you type, to twelve significant digits.
What is the formula for kJ to kcal?: For thermochemical kilocalories, kcal = kJ / 4.184. Multiplying by the rounded reciprocal 0.239005736138 only approximates that division and can change final rounding. In reverse, kJ = kcal × 4.184: 100 kcal is exactly 418.4 kJ, 250 kcal exactly 1,046 kJ and 2,000 kcal exactly 8,368 kJ. Exact terminating factors can still produce long outputs that round to twelve significant digits. Swap units reverses the pair and keeps the typed scalar.
Why does a food label print two energy numbers?: A source can show one energy quantity in kilojoules and kilocalories. A food Calorie commonly means a kilocalorie, but labels, calorie conventions and calculation rules vary. For an explicitly supplied thermochemical kcal quantity, 1 kcal is exactly 4.184 kJ. The converter uses that stated definition; it cannot determine a label’s jurisdiction, rounding or method for deriving its energy figures.
Why do the kJ and kcal on my pack not divide out to exactly 4.184?: Separately rounded values or independently calculated energy figures can yield a different ratio. For example, 670 kJ converts here to 160.133843212 thermochemical kcal; a printed pair 670 kJ and 160 kcal therefore need not retain an exact 4.184 ratio. If a supplied factor table uses 17 kJ/g alongside 4 kcal/g, its ratio is 4.25; 37 kJ/g alongside 9 kcal/g gives about 4.11. Those are arithmetic examples, not a finding about your pack or proof that it is correct. This converter cannot identify the source’s factors, rounding rules or calorie convention.
Is a kcal the same as a Calorie with a capital C?: Food Calorie commonly means a kilocalorie, 1,000 small calories under the same definition. Check the source’s convention. Here the Calorie (cal) is thermochemical, exactly 4.184 J, and Kilocalorie (kcal) exactly 4,184 J. Thus a stated 250 thermochemical kcal is exactly 1,046 kJ, and 1,000 kJ displays as 239,005.736138 cal or 239.005736138 kcal. Choose the explicit unit your source documents rather than relying on capitalization alone.
Which calorie does food energy use, 4.184 or 4.1868?: This converter uses the thermochemical calorie of exactly 4.184 J and its kilocalorie of exactly 4,184 J. The International Table calorie is exactly 4.1868 J, about 0.0669% larger. With the thermochemical definition 2,000 kJ displays as 478.011472275 kcal; divided by 4.1868 it gives 477.691793255 IT kcal, about 0.32 kcal less. IT kcal is absent from the menu. The tool cannot establish which definition or calculation rules an external food-energy source uses.
Is dividing by 4.2 close enough?: Dividing by 4.2 is about 0.38% below the thermochemical conversion: 1,000 / 4.2 displays as 238.095238095 kcal, while 1,000 / 4.184 displays as 239.005736138 kcal. Multiplying by 0.24 is about 0.42% high and gives 240 kcal for the same 1,000 kJ. These are approximations; choose the precision needed for the stated calculation. The displayed values from division by 4.184 still round to twelve significant digits.
What else does this page show, and why does it open on kJ and kcal?: The other common energy units appear below, using thermochemical cal/kcal and IT BTU. For 1,000 kJ, outputs include 277.777777778 Wh, 0.277777777778 kWh and 947.817120313 BTU; Show 1 more adds electronvolts. This focused page opens on Kilojoule and Kilocalorie, while preserving the main converter’s saved unit pair. When storage is usable, a saved value and uncommon-unit preference can travel between pages. Its suffix must still match From. Valid deliberate scalar edits can save those fields after a short delay; invalid or incomplete drafts preserve the saved record. Unusable or conflicting records remain until you use Forget saved settings, which keeps the current conversion on screen. Copy result copies the displayed headline without digit-grouping commas; each visible conversion row has its own Copy button. Displayed and copied values round to twelve significant digits. If native copying fails, a complete selectable summary identifies the input, selected pair and conventions and includes every unit in the category, including uncommon units. Your input and converted values are calculated in the browser and are not uploaded by the converter. The definitions arrive with the page, so conversion needs no external data lookup and keeps working offline after the page has loaded. The core conversion needs no account.

Results round to 12 significant digits using the listed unit conventions. Many factors are exact definitions; psi and parsec use rounded coefficients. Temperature includes scale offsets. Days and weeks are fixed-duration units, and unit conversion does not determine calendar dates, ambient pressure or a software label’s convention.