Rømer to Kelvin (°Rø to K)
1 degree Rømer equals 260.7690476 kelvins.
How to convert degrees Rømer to kelvins
Converting degrees Rømer to kelvins is not a simple multiplication, so use the formula below.
K = °Rø × 1.904761905 + 258.8642857
Example: 10 degrees Rømer = 277.9119048 kelvins.
Temperature scales have different zero points, so converting is not just multiplication. Differences in degrees convert differently from absolute readings.
About these units
Degree Rømer (°Rø)
An early temperature scale devised by Ole Rømer around 1702: water freezes at 7.5° and boils at 60°. Fahrenheit based his scale on it.
Ole Rømer, the Danish astronomer better known for measuring the speed of light, devised this scale around 1702 for his own use. It is the second temperature scale on record, after Newton's from a year earlier. Water freezes at 7.5 degrees and boils at 60 degrees, so one degree equals 40/21 of a Celsius degree, about 1.905 degrees Celsius.
The odd 7.5 may come from his earlier choice of a lower fixed point, the cold of ammonium chloride brine. He apparently found that the freezing point of water lay about one eighth of the way up from that mark to boiling and moved the scale accordingly, though his exact reasoning is unknown.
Daniel Fahrenheit visited him in Copenhagen in 1708 and by 1713 was making thermometers on a scale largely borrowed from Rømer. He shifted freezing from 7.5 to 8 and quartered each degree, which gave 32 degrees. Rømer's notebook was only published in 1910.
0 degrees Rømer = 258.8642857 kelvins (approximately).
Sources: Wikipedia: Rømer scale; Wikipedia: Ole Rømer
Kelvin (K)
The SI base unit of temperature. Zero kelvin is absolute zero, where particles have minimal thermal motion. A kelvin step is the same size as a Celsius degree.
Lord Kelvin, born William Thomson, published an absolute temperature scale in 1848 and refined it with James Joule in 1854. Its zero sits at absolute zero, and its degree is the same size as a Celsius degree. The kelvin entered the SI in 1954, defined as 1/273.16 of the thermodynamic temperature of the triple point of water, where ice, liquid and vapor coexist. In 1967 the 13th CGPM renamed the unit from the degree Kelvin to simply the kelvin, with symbol K, and no word degree.
Since 20 May 2019 the kelvin has been defined by fixing the Boltzmann constant at exactly 1.380649 times 10 to the minus 23 joule per kelvin, which frees it from the properties of any one substance. Scientists use it for stars and cryogenics, and lighting designers use it for color temperature. NIST notes that incandescent bulbs run near 3,000 K, daylight lamps at 5,000 to 5,600 K, and the Sun's surface at about 5,800 K. Room temperature, about 21 degrees Celsius, is roughly 294 K.
The kelvin is the reference unit for temperature on this site.
Sources: NIST: the kelvin and the SI redefinition; BIPM: 13th CGPM (1967), Resolution 3; Wikipedia: Kelvin
Related conversions
- Kelvin to Rømer (reverse)
- Rømer to Celsius
- Rømer to Fahrenheit
- Celsius to kelvin
- Fahrenheit to kelvin
- Rankine to kelvin
- Réaumur to kelvin
- Delisle to kelvin
- Newton to kelvin
See all temperature units.