Hartree to BTU (IT) Converter
Convert Hartree (Eh) to BTU (IT) (BTU (IT)) instantly. 1 Eh = 4.132241e-21 BTU (IT).
Energy Converter
27 units available
1 Eh = 4.132241e-21 BTU (IT)
Formula:
BTU (IT) = Eh × 4.132241e-21With your value: 1 Eh = 4.132241e-21 BTU (IT)
How big is that?
Everyday references on a logarithmic scale, all expressed in hartree so you can sanity-check the result.
Other Hartree to BTU (IT) conversions
Hartree to BTU (IT) Conversion Table
| Hartree (Eh) | BTU (IT) (BTU (IT)) |
|---|---|
| 0.5 | 2.066120e-21 |
| 1 | 4.132241e-21 |
| 2 | 8.264481e-21 |
| 5 | 2.066120e-20 |
| 10 | 4.132241e-20 |
| 15 | 6.198361e-20 |
| 20 | 8.264481e-20 |
| 25 | 1.033060e-19 |
| 50 | 2.066120e-19 |
| 100 | 4.132241e-19 |
| 250 | 1.033060e-18 |
| 500 | 2.066120e-18 |
| 1000 | 4.132241e-18 |
BTU (IT) to Hartree Conversion Table
| BTU (IT) (BTU (IT)) | Hartree (Eh) |
|---|---|
| 0.5 | 1.209997e+20 |
| 1 | 2.419995e+20 |
| 2 | 4.839989e+20 |
| 5 | 1.209997e+21 |
| 10 | 2.419995e+21 |
| 15 | 3.629992e+21 |
| 20 | 4.839989e+21 |
| 25 | 6.049986e+21 |
| 50 | 1.209997e+22 |
| 100 | 2.419995e+22 |
| 250 | 6.049986e+22 |
| 500 | 1.209997e+23 |
| 1000 | 2.419995e+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
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
BTU (IT) (BTU (IT))
Energy
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 BTU (IT)
To convert from Hartree (Eh) to BTU (IT) (BTU (IT)), multiply the value by 4.132241e-21.
Formula: BTU (IT) = Eh × 4.132241e-21
Reverse: Eh = BTU (IT) × 2.419995e+20
Step-by-Step Example
- Start with your value in Hartree. For example: 5 Eh
- Multiply by the conversion factor: 5 x 4.132241e-21
- The result is: 2.066120e-20 BTU (IT)
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 BTU (IT)
The btu (it) (BTU (IT)) is a unit of energy and work. One btu (it) equals 1055.055853 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 BTU (IT) are in 1 Hartree?
There are exactly 4.132241e-21 BTU (IT) in 1 Hartree. This means the conversion factor from Hartree to BTU (IT) is 4.132241e-21.
What is the formula to convert Hartree to BTU (IT)?
The formula to convert Hartree to BTU (IT) is: BTU (IT) = Eh × 4.132241e-21. For example, to convert 10 Hartree to BTU (IT), you would multiply 10 by 4.132241e-21.
What is a 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.
What is a BTU (IT)?
The btu (it) (BTU (IT)) is a unit of energy and work. One btu (it) equals 1055.055853 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.
What are the common uses of Hartree?
The Hartree is commonly used in energy calculations, engineering and science, education.
Related Energy Conversions
Cite this page
UnitConvertLab. (2026). Hartree to BTU (IT) converter. UnitConvertLab. Retrieved from https://unitconvertlab.com/convert/hartree-to-btu_it