Convert Rømer to Electronvolt
Convert degrees rømer to electronvolts instantly. eV = (°Rø × 0.0001641396812) + 0.0223071982 — use the live calculator, the exact formula, a reference-temperature table and worked examples. Also check the Electronvolt to Rømer converter for the reverse conversion.
Units explained
Rømer
The degree Rømer (°Rø) sets the freezing point of water at 7.5 °Rø and the boiling point at 60 °Rø; one degree Rømer equals exactly 40/21 of a kelvin (about 1.905 K).
Created by Danish astronomer Ole Rømer — famous for making the first quantitative measurement of the speed of light — who set 0 °Rø at the temperature of a salt-ice brine and 60 °Rø at boiling water.
Of historical rather than practical importance: it is remembered as the direct ancestor of the Fahrenheit scale and appears mainly in the history of science and in metrology coursework.
Devised by Ole Rømer in Copenhagen, Denmark, in 1701; Daniel Fahrenheit visited Rømer in 1708 and adapted this scale into his own.
Electronvolt
As a temperature unit, one electronvolt (eV) is the temperature at which a particle's characteristic thermal energy kT equals one electronvolt — exactly 11,604.51812 kelvins under the 2019 SI definitions of e and k.
Comes from the plasma-physics and astrophysics habit of quoting temperatures directly as energies through the Boltzmann relation E = kT, which removes constant unit conversions from the equations of hot ionized matter.
Standard in plasma physics, fusion research, and high-energy astrophysics: the core plasma of a tokamak runs at tens of kiloelectronvolts, while the Sun's core is about 1.3 keV.
Grew out of 20th-century particle- and plasma-physics convention; its kelvin equivalent became an exact number when the 2019 SI revision fixed both the elementary charge and the Boltzmann constant.
Rømer to Electronvolt conversion formula
The exact relationship between degrees rømer and electronvolts:
To convert degrees rømer to electronvolts, multiply the value by 0.0001641396812, then add 0.0223071982. To reverse, multiply the value by 6092.372014, then subtract 135.90375.
Reference anchors: water freezes at 7.5 °Rø = 0.0235382458 eV and boils at 60 °Rø = 0.0321555791 eV (at standard atmospheric pressure).
How to use this converter
Type a value into the calculator. The result in electronvolts updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Electronvolt to Rømer converter for the reverse direction.
Step-by-step: convert degrees rømer to electronvolts
- Write down the temperature in degrees rømer (°Rø).
- Multiply the value by 0.0001641396812, then add 0.0223071982.
- The result is the same temperature expressed in electronvolts (eV).
- To reverse, multiply the value by 6092.372014, then subtract 135.90375 — or open the Electronvolt to Rømer converter.
Worked examples
Example 1 — Convert 26.925 °Rø to eV (human body temperature):
(26.925 × 0.0001641396812) + 0.0223071982 = 0.0267266591 eV
Example 2 — Convert 60 °Rø to eV (the boiling point of water):
(60 × 0.0001641396812) + 0.0223071982 = 0.0321555791 eV
Rømer to Electronvolt conversion table
Physically meaningful reference temperatures, from absolute zero to the surface of the Sun, converted from degrees rømer to electronvolts:
| Rømer [°Rø] | Electronvolt [eV] | Reference point |
|---|---|---|
| -135.90375 | 0 | Absolute zero |
| -13.5 | 0.0200913125 | Where Celsius and Fahrenheit coincide (−40°) |
| -1.8333333333 | 0.0220062754 | Zero Fahrenheit (0 °F) |
| 7.5 | 0.0235382458 | Water freezes (0 °C / 32 °F) |
| 7.50525 | 0.0235391075 | Triple point of water |
| 12.75 | 0.0243999791 | Cool day (10 °C / 50 °F) |
| 18 | 0.0252617125 | Room temperature (20 °C / 68 °F) |
| 20.625 | 0.0256925791 | Standard laboratory temperature (25 °C) |
| 23.25 | 0.0261234458 | Hot day (30 °C / 86 °F) |
| 26.925 | 0.0267266591 | Human body temperature (37 °C / 98.6 °F) |
| 28.5 | 0.0269851791 | Heat-wave day (40 °C / 104 °F) |
| 33.75 | 0.0278469124 | Hot tap water (50 °C / 122 °F) |
| 60 | 0.0321555791 | Water boils (100 °C / 212 °F) |
| 102 | 0.0390494457 | Moderate baking oven (180 °C / 356 °F) |
| 2897.54625 | 0.4979095159 | Surface of the Sun (≈5,505 °C) |
Frequently asked questions
What is 26.925 °Rø in eV?
How do I convert degrees rømer to electronvolts?
How do I convert electronvolts back to degrees rømer?
At what temperature do the Rømer and Electronvolt scales read the same number?
Can a temperature be below absolute zero?
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Scientific & Fixed-Point (3 units)
SI Prefixed Kelvin (5 units)
Sources & references
Conversion relationship (eV = (°Rø × 0.0001641396812) + 0.0223071982) verified against the following authoritative sources:
- BIPM — The International System of Units (SI Brochure 9th ed.)
Official BIPM publication defining the seven SI base units (including the meter) and the rules for their use. The global authority on units of measurement.
- NIST — Guide to the SI
US National Institute of Standards and Technology reference covering the SI base and derived units with definitions and usage rules for US technical practice.
- NIST Special Publication 811 — Guide for the Use of the International System of Units
Detailed NIST guide covering exact conversion factors between SI and US customary units along with formatting and rounding conventions.
- BIPM — International Temperature Scale of 1990 (ITS-90)
The internationally agreed practical temperature scale, defining fixed points (including the triple point of water at 273.16 K) and interpolation instruments used by national metrology institutes for thermometer calibration worldwide.
- CODATA Internationally Recommended Values of the Fundamental Physical Constants
Committee on Data of the International Science Council; authoritative source for the masses of fundamental particles (electron, proton, neutron) and the atomic mass constant.