Ha to cal Converter - Hartree to Calorie

Hartree (Ha) to Calorie (cal)

Direct answer

1 Ha = 1.042004e-18 cal

cal = Ha × 1.042004e-18

Converter

Input

Result

1.042004e-18cal

cal = Ha × 1.042004e-18

Ha = cal × 9.59689217e+17

Example: 10 Ha = 10 × 1.042004e-18 = 1.042004e-17 cal.

Express both Ha and cal in the same base unit J (joule), then cancel the shared base unit.

1
Rewrite Ha in the base unit
$1 Ha = 4.35974472 \times 1 0^{- 18} J$
2
Rewrite cal in the base unit
$1 cal = 4.184 J$
3
Forward conversion
$1 Ha = \frac{4.35974472 \times 1 0 ^{- 18} J}{4.184 J} \times 1 cal = \frac{4.35974472 \times 1 0 ^{- 18}}{4.184} cal = 1.042004 \times 1 0^{- 18} cal$
4
Reverse conversion
$1 cal = \frac{4.184 J}{4.35974472 \times 1 0 ^{- 18} J} \times 1 Ha = \frac{4.184}{4.35974472 \times 1 0 ^{- 18}} Ha = 9.59689217 \times 1 0^{17} Ha$

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Guarded output

AI text is for interpretation only. The page calculator remains the source of truth for numeric results.

1 Ha = 1.042004e-18 cal.

10 Ha = 1.042004e-17 cal.

100 Ha = 1.042004e-16 cal.

Use cal = Ha × 1.042004e-18.

1 cal = 9.59689217e+17 Ha.

Use the conversion factor and round the result to the precision required by your calculation.