Temperature · Unit Converter

Convert Electronvolt to Rømer

Convert electronvolts to degrees rømer instantly. °Rø = (eV × 6092.372014) − 135.90375 — use the live calculator, the exact formula, a reference-temperature table and worked examples. Also check the Rømer to Electronvolt converter for the reverse conversion.

Written by Sunith Babu L, Ph.D., Lead Engineer Reviewed by Girish V Kulkarni Ph.D.
Temperature category 2 min read Published Last reviewed Updated

Units explained

Scientific & Fixed-Point

Electronvolt

What is an 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.

Origin of the electronvolt

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.

Where it is used

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.

When and where it was developed

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.

Historical Scales

Rømer

What is a degree 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).

Origin of the degree rømer

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.

Where it is used

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.

When and where it was developed

Devised by Ole Rømer in Copenhagen, Denmark, in 1701; Daniel Fahrenheit visited Rømer in 1708 and adapted this scale into his own.

Electronvolt to Rømer conversion formula

The exact relationship between electronvolts and degrees rømer:

°Rø = (eV × 6092.372014) − 135.90375
eV = (°Rø × 0.0001641396812) + 0.0223071982

To convert electronvolts to degrees rømer, multiply the value by 6092.372014, then subtract 135.90375. To reverse, multiply the value by 0.0001641396812, then add 0.0223071982.

Reference anchors: water freezes at 0.0235382458 eV = 7.5 °Rø and boils at 0.0321555791 eV = 60 °Rø (at standard atmospheric pressure).

How to use this converter

Type a value into the calculator. The result in degrees rømer updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Rømer to Electronvolt converter for the reverse direction.

Step-by-step: convert electronvolts to degrees rømer

  1. Write down the temperature in electronvolts (eV).
  2. Multiply the value by 6092.372014, then subtract 135.90375.
  3. The result is the same temperature expressed in degrees rømer (°Rø).
  4. To reverse, multiply the value by 0.0001641396812, then add 0.0223071982 — or open the Rømer to Electronvolt converter.

Worked examples

Example 1 — Convert 1 eV to °Rø:
(1 × 6092.372014) − 135.90375 = 5956.4682638138 °Rø

Example 2 — Convert 100 eV to °Rø:
(100 × 6092.372014) − 135.90375 = 609101.2976313793 °Rø

Electronvolt to Rømer conversion table

Physically meaningful reference temperatures, from absolute zero to the surface of the Sun, converted from electronvolts to degrees rømer:

Electronvolt [eV]Rømer [°Rø]Reference point
0-135.90375Absolute zero
0.0200913125-13.5Where Celsius and Fahrenheit coincide (−40°)
0.0220062754-1.8333333333Zero Fahrenheit (0 °F)
0.02353824587.5Water freezes (0 °C / 32 °F)
0.02353910757.50525Triple point of water
0.024399979112.75Cool day (10 °C / 50 °F)
0.025261712518Room temperature (20 °C / 68 °F)
0.025692579120.625Standard laboratory temperature (25 °C)
0.026123445823.25Hot day (30 °C / 86 °F)
0.026726659126.925Human body temperature (37 °C / 98.6 °F)
0.026985179128.5Heat-wave day (40 °C / 104 °F)
0.027846912433.75Hot tap water (50 °C / 122 °F)
0.032155579160Water boils (100 °C / 212 °F)
0.0390494457102Moderate baking oven (180 °C / 356 °F)
0.49790951592897.54625Surface of the Sun (≈5,505 °C)

Frequently asked questions

What is 1 eV in °Rø?
1 eV equals 5956.4682638138 °Rø — normal human body temperature.
How do I convert electronvolts to degrees rømer?
Use the formula °Rø = (eV × 6092.372014) − 135.90375: multiply the value by 6092.372014, then subtract 135.90375.
How do I convert degrees rømer back to electronvolts?
Apply the reverse formula eV = (°Rø × 0.0001641396812) + 0.0223071982 — multiply the value by 0.0001641396812, then add 0.0223071982 — or use the Rømer to Electronvolt converter.
At what temperature do the Electronvolt and Rømer scales read the same number?
Both scales show the same number at 0.0223108603: 0.0223108603 eV = 0.0223108603 °Rø. Set °Rø = eV in the conversion formula and solve to verify it.
Can a temperature be below absolute zero?
No. Absolute zero (0 K = −273.15 °C = −459.67 °F) is the floor of the thermodynamic temperature scale. The calculator flags any input that would fall below it.

Convert Electronvolt to other temperature units

Show all Electronvolt conversions

Sources & references

Conversion relationship (°Rø = (eV × 6092.372014) − 135.90375) verified against the following authoritative sources:

Results are provided for general reference. Verify critical measurements against an authoritative standard.