Temperature · Unit Converter

Convert Millikelvin to Réaumur

Convert millikelvins to degrees réaumur instantly. °Ré = (mK × 0.0008) − 218.52 — use the live calculator, the exact formula, a reference-temperature table and worked examples. Also check the Réaumur to Millikelvin 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

SI Prefixed Kelvin

Millikelvin

What is a millikelvin?

One millikelvin (mK) is one thousandth of a kelvin (10⁻³ K), measured upward from absolute zero.

Origin of the millikelvin

Formed with the SI prefix 'milli-' (from Latin 'mille', a thousand) applied to the kelvin base unit.

Where it is used

Cryogenics and low-temperature physics — the dilution refrigerators that cool superconducting quantum computers operate at roughly 10–20 mK.

When and where it was developed

The milli- prefix belongs to the original metric system of 1795 and was carried into the SI in 1960; the kelvin became an SI base unit in 1954.

Historical Scales

Réaumur

What is a degree réaumur?

The degree Réaumur (°Ré) sets the freezing point of water at 0 °Ré and the boiling point at 80 °Ré, so one degree Réaumur equals exactly 1.25 kelvins (5/4 K).

Origin of the degree réaumur

Devised by French scientist René Antoine Ferchault de Réaumur using alcohol thermometers whose working liquid expanded 80 parts per thousand between the freezing and boiling points of water — the origin of the 80-degree span.

Where it is used

Once dominant across 18th- and 19th-century Europe, especially France, Germany, and Russia. It survives today mainly in traditional cheese-making — Parmigiano-Reggiano and Swiss alpine dairies still specify milk temperatures in °Ré.

When and where it was developed

Introduced by Réaumur in Paris in 1730; it faded from general use after France adopted the Celsius scale with the metric system in the 1790s.

Millikelvin to Réaumur conversion formula

The exact relationship between millikelvins and degrees réaumur:

°Ré = (mK × 0.0008) − 218.52
mK = (°Ré × 1250) + 273150

To convert millikelvins to degrees réaumur, multiply the value by 0.0008, then subtract 218.52. To reverse, multiply the value by 1250, then add 273150.

Reference anchors: water freezes at 273150 mK = 0 °Ré and boils at 373150 mK = 80 °Ré (at standard atmospheric pressure).

How to use this converter

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

Step-by-step: convert millikelvins to degrees réaumur

  1. Write down the temperature in millikelvins (mK).
  2. Multiply the value by 0.0008, then subtract 218.52.
  3. The result is the same temperature expressed in degrees réaumur (°Ré).
  4. To reverse, multiply the value by 1250, then add 273150 — or open the Réaumur to Millikelvin converter.

Worked examples

Example 1 — Convert 1 mK to °Ré:
(1 × 0.0008) − 218.52 = -218.5192 °Ré

Example 2 — Convert 100 mK to °Ré:
(100 × 0.0008) − 218.52 = -218.44 °Ré

Millikelvin to Réaumur conversion table

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

Millikelvin [mK]Réaumur [°Ré]Reference point
0-218.52Absolute zero
233150-32Where Celsius and Fahrenheit coincide (−40°)
255372.2222222222-14.2222222222Zero Fahrenheit (0 °F)
2731500Water freezes (0 °C / 32 °F)
2731600.008Triple point of water
2831508Cool day (10 °C / 50 °F)
29315016Room temperature (20 °C / 68 °F)
29815020Standard laboratory temperature (25 °C)
30315024Hot day (30 °C / 86 °F)
31015029.6Human body temperature (37 °C / 98.6 °F)
31315032Heat-wave day (40 °C / 104 °F)
32315040Hot tap water (50 °C / 122 °F)
37315080Water boils (100 °C / 212 °F)
453150144Moderate baking oven (180 °C / 356 °F)
57780004403.88Surface of the Sun (≈5,505 °C)

Frequently asked questions

What is 1 mK in °Ré?
1 mK equals -218.5192 °Ré — normal human body temperature.
How do I convert millikelvins to degrees réaumur?
Use the formula °Ré = (mK × 0.0008) − 218.52: multiply the value by 0.0008, then subtract 218.52.
How do I convert degrees réaumur back to millikelvins?
Apply the reverse formula mK = (°Ré × 1250) + 273150 — multiply the value by 1250, then add 273150 — or use the Réaumur to Millikelvin converter.
At what temperature do the Millikelvin and Réaumur scales read the same number?
Both scales show the same number at -218.6949559648: -218.6949559648 mK = -218.6949559648 °Ré. Set °Ré = mK 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 Millikelvin to other temperature units

Show all Millikelvin conversions

Sources & references

Conversion relationship (°Ré = (mK × 0.0008) − 218.52) verified against the following authoritative sources:

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