Temperature · Unit Converter

Convert Rømer to Fahrenheit

Convert degrees rømer to degrees fahrenheit instantly. °F = (°Rø × 24/7) + 6.2857142857 — use the live calculator, the exact formula, a reference-temperature table and worked examples. Also check the Fahrenheit to Rømer 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

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.

Modern Standard Scales

Fahrenheit

What is a degree fahrenheit?

The degree Fahrenheit (°F) sets the freezing point of water at 32 °F and the boiling point at 212 °F, dividing the interval into 180 equal degrees. One degree Fahrenheit is exactly 5/9 the size of a kelvin, and °F = °C × 9/5 + 32 exactly.

Origin of the degree fahrenheit

Created by German-born physicist Daniel Gabriel Fahrenheit, inventor of the reliable mercury-in-glass thermometer. His zero point was the temperature of an ice-and-salt brine mixture, and his original upper fixed point sat near human body temperature.

Where it is used

The official everyday scale of the United States and a handful of other countries. In India, clinical thermometers and fever readings are still very commonly quoted in Fahrenheit (a '102-degree fever'), which keeps °F to °C conversion a daily need.

When and where it was developed

Introduced by Daniel Gabriel Fahrenheit in 1724 in Amsterdam, building directly on Ole Rømer's earlier scale, which Fahrenheit had studied during a 1708 visit to Copenhagen.

Rømer to Fahrenheit conversion formula

The exact relationship between degrees rømer and degrees fahrenheit:

°F = (°Rø × 24/7) + 6.2857142857
°Rø = (°F × 7/24) − 1.8333333333

To convert degrees rømer to degrees fahrenheit, multiply the value by 24/7, then add 6.2857142857. To reverse, multiply the value by 7/24, then subtract 1.8333333333.

Reference anchors: water freezes at 7.5 °Rø = 32 °F and boils at 60 °Rø = 212 °F (at standard atmospheric pressure).

How to use this converter

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

Step-by-step: convert degrees rømer to degrees fahrenheit

  1. Write down the temperature in degrees rømer (°Rø).
  2. Multiply the value by 24/7, then add 6.2857142857.
  3. The result is the same temperature expressed in degrees fahrenheit (°F).
  4. To reverse, multiply the value by 7/24, then subtract 1.8333333333 — or open the Fahrenheit to Rømer converter.

Worked examples

Example 1 — Convert 26.925 °Rø to °F (human body temperature):
(26.925 × 24/7) + 6.2857142857 = 98.6 °F

Example 2 — Convert 60 °Rø to °F (the boiling point of water):
(60 × 24/7) + 6.2857142857 = 212 °F

Rømer to Fahrenheit conversion table

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

Rømer [°Rø]Fahrenheit [°F]Reference point
-135.90375-459.67Absolute zero
-13.5-40Where Celsius and Fahrenheit coincide (−40°)
-1.83333333330Zero Fahrenheit (0 °F)
7.532Water freezes (0 °C / 32 °F)
7.5052532.018Triple point of water
12.7550Cool day (10 °C / 50 °F)
1868Room temperature (20 °C / 68 °F)
20.62577Standard laboratory temperature (25 °C)
23.2586Hot day (30 °C / 86 °F)
26.92598.6Human body temperature (37 °C / 98.6 °F)
28.5104Heat-wave day (40 °C / 104 °F)
33.75122Hot tap water (50 °C / 122 °F)
60212Water boils (100 °C / 212 °F)
102356Moderate baking oven (180 °C / 356 °F)
2897.546259940.73Surface of the Sun (≈5,505 °C)

Frequently asked questions

What is 26.925 °Rø in °F?
26.925 °Rø equals 98.6 °F — normal human body temperature.
How do I convert degrees rømer to degrees fahrenheit?
Use the formula °F = (°Rø × 24/7) + 6.2857142857: multiply the value by 24/7, then add 6.2857142857.
How do I convert degrees fahrenheit back to degrees rømer?
Apply the reverse formula °Rø = (°F × 7/24) − 1.8333333333 — multiply the value by 7/24, then subtract 1.8333333333 — or use the Fahrenheit to Rømer converter.
At what temperature do the Rømer and Fahrenheit scales read the same number?
Both scales show the same number at -2.5882352941: -2.5882352941 °Rø = -2.5882352941 °F. Set °F = °Rø 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 Rømer to other temperature units

Show all Rømer conversions

Sources & references

Conversion relationship (°F = (°Rø × 24/7) + 6.2857142857) verified against the following authoritative sources:

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