Hartree to Kilojoule Converter

Energy Converter

27 units available

Decimals:

From

To

4.359745e-21

1 Eh = 4.359745e-21 kJ

Formula:

kJ = Eh × 4.359745e-21

With your value: 1 Eh = 4.359745e-21 kJ

How big is that?

Everyday references on a logarithmic scale, all expressed in hartree so you can sanity-check the result.

Your value1.00 Eh

Heartbeat (2.3e+17× your value)2.29e+17 Eh

AA battery charge (2.3e+21× your value)2.29e+21 Eh

Slice of bread (6.4e+22× your value)6.42e+22 Eh

Daily food intake (1.9e+24× your value)1.93e+24 Eh

Litre of petrol (7.8e+24× your value)7.84e+24 Eh

Other Hartree to Kilojoule conversions

2 Eh to kJ 3 Eh to kJ 4 Eh to kJ 5 Eh to kJ 6 Eh to kJ 7 Eh to kJ 8 Eh to kJ

Hartree to Kilojoule Conversion Table

Hartree (Eh)	Kilojoule (kJ)
0.5	2.179872e-21
1	4.359745e-21
2	8.719489e-21
5	2.179872e-20
10	4.359745e-20
15	6.539617e-20
20	8.719489e-20
25	1.089936e-19
50	2.179872e-19
100	4.359745e-19
250	1.089936e-18
500	2.179872e-18
1000	4.359745e-18

Kilojoule to Hartree Conversion Table

Kilojoule (kJ)	Hartree (Eh)
0.5	1.146856e+20
1	2.293712e+20
2	4.587425e+20
5	1.146856e+21
10	2.293712e+21
15	3.440568e+21
20	4.587425e+21
25	5.734281e+21
50	1.146856e+22
100	2.293712e+22
250	5.734281e+22
500	1.146856e+23
1000	2.293712e+23

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.

Hartree (Eh)

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

Kilojoule (kJ)

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 Hartree to Kilojoule

To convert from Hartree (Eh) to Kilojoule (kJ), multiply the value by 4.359745e-21.

Formula: kJ = Eh × 4.359745e-21

Reverse: Eh = kJ × 2.293712e+20

Step-by-Step Example

Start with your value in Hartree. For example: 5 Eh
Multiply by the conversion factor: 5 x 4.359745e-21
The result is: 2.179872e-20 kJ

About Hartree

The hartree (Eh) is a unit of energy and work. One hartree equals 4.359745 × 10^-18 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 Kilojoule

The kilojoule (kJ) is a unit of energy and work. One kilojoule equals 1000 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 Kilojoule are in 1 Hartree?

There are exactly 4.359745e-21 Kilojoule in 1 Hartree. This means the conversion factor from Hartree to Kilojoule is 4.359745e-21.

What is the formula to convert Hartree to Kilojoule?

The formula to convert Hartree to Kilojoule is: kJ = Eh × 4.359745e-21. For example, to convert 10 Hartree to Kilojoule, you would multiply 10 by 4.359745e-21.

What is a Hartree?