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    Energy Conversion

    1 Hartree to Kilojoule

    Quick answer

    1 Hartree (Eh) equals

    4.359745e-21 kJ

    To convert 1 Hartrees to Kilojoules, multiply by 4.359745e-21. Therefore, 1 Hartree (Eh) equals 4.359745e-21 Kilojoule (kJ).

    Formula: kJ = Eh × 4.359745e-21. Calculation: 1 × 4.359745e-21 = 4.359745e-21 kJ.

    Convert Hartree (Eh) to Kilojoule (kJ) online with our free unit converter. In energy, 1 Eh = 4.359745e-21 kJ. Explore step-by-step conversion steps, mathematical formulas, and quick conversion reference tables below.

    Worked example: converting Hartree to Kilojoule

    1. Step 1 — start with the formula. kJ = Eh × 4.359745e-21
    2. Step 2 — substitute your figure. 1 Eh × 4.359745e-21
    3. Step 3 — read the result. 1 Eh = 4.359745e-21 kJ
    4. Step 4 — check it in reverse. Eh = kJ × 2.293712e+20 returns 1 Eh, which matches the figure you started with.

    Energy Converter

    27 units available

    Decimals:
    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 kJ3 Eh to kJ4 Eh to kJ5 Eh to kJ6 Eh to kJ7 Eh to kJ8 Eh to kJFull Hartree to Kilojoule converter

    Hartree to Kilojoule Conversion Table

    Hartree (Eh)Kilojoule (kJ)
    0.52.179872e-21
    14.359745e-21
    28.719489e-21
    52.179872e-20
    104.359745e-20
    156.539617e-20
    208.719489e-20
    251.089936e-19
    502.179872e-19
    1004.359745e-19
    2501.089936e-18
    5002.179872e-18
    10004.359745e-18

    Kilojoule to Hartree Conversion Table

    Kilojoule (kJ)Hartree (Eh)
    0.51.146856e+20
    12.293712e+20
    24.587425e+20
    51.146856e+21
    102.293712e+21
    153.440568e+21
    204.587425e+21
    255.734281e+21
    501.146856e+22
    1002.293712e+22
    2505.734281e+22
    5001.146856e+23
    10002.293712e+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

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

    Hartree and Kilojoule Relationship

    This calculation facilitates standardized conversion between recognized units of energy. Since 1 Hartree represents a fraction of a Kilojoule (1 Kilojoule ≈ 2.294e+20 Hartrees), the Kilojoule is the larger measurement interval. Understanding the relationship between Hartree and Kilojoule is essential for accurate calculations in physics, engineering, commerce, and daily applications.

    About Hartree

    The Hartree (symbol: Eh) is a recognized unit in the Standard measurement framework, utilized within energy applications for precision and standardized data representation.

    Common uses of Hartree: energy calculations, engineering and science, education.

    About Kilojoule

    The Kilojoule (symbol: kJ) is a recognized unit in the Metric (SI) measurement framework, utilized within energy applications for precision and standardized data representation.

    Common uses of Kilojoule: energy calculations, engineering and science, education.

    Frequently Asked Questions

    What is 1 Hartree in Kilojoule?
    1 Hartree equals 4.359745e-21 Kilojoule.
    How many Kilojoules are in 1 Hartree?
    There are exactly 4.359745e-21 Kilojoules 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 Hartrees to Kilojoules, you would multiply 10 by 4.359745e-21.
    What is a Hartree?
    The Hartree (symbol: Eh) is a recognized unit in the Standard measurement framework, utilized within energy applications for precision and standardized data representation.
    What is a Kilojoule?
    The Kilojoule (symbol: kJ) is a recognized unit in the Metric (SI) measurement framework, utilized within energy applications for precision and standardized data representation.
    What are the common uses of Hartree?
    The Hartree is commonly used in energy calculations, engineering and science, education.

    Related Energy Conversions

    Joule → KilojouleMegajoule → KilojouleGigajoule → KilojouleMillijoule → KilojouleCalorie (th) → KilojouleCalorie (IT) → KilojouleKilocalorie → KilojouleBTU (th) → KilojouleBTU (IT) → Kilojoule

    Cite this page

    UnitConvertLab. (2026). 1 Hartree to Kilojoule. UnitConvertLab. Retrieved from https://unitconvertlab.com/convert/1-hartree-to-kilojoule