Convert Rankine to Gigakelvin
Convert degrees rankine to gigakelvins instantly. 1 °R = 5.555556e-10 GK — use the live calculator, the exact formula, a reference-temperature table and worked examples. Also check the Gigakelvin to Rankine converter for the reverse conversion.
Units explained
Rankine
The degree Rankine (°R) is the absolute counterpart of the Fahrenheit scale: 0 °R is absolute zero, and one degree Rankine is exactly the same size as one degree Fahrenheit (5/9 of a kelvin). Water freezes at 491.67 °R.
Named for William John Macquorn Rankine, the Scottish engineer and physicist who proposed an absolute scale built from Fahrenheit-sized degrees, paralleling Kelvin's absolute scale built from Celsius-sized degrees.
Used mainly in United States aerospace, thermodynamics, and power-plant engineering, where calculations demand absolute temperature but legacy data, instruments, and codes are in Fahrenheit.
Proposed by W. J. M. Rankine at the University of Glasgow in 1859, eleven years after Lord Kelvin's absolute scale of 1848.
Gigakelvin
One gigakelvin (GK) is one billion kelvins (10⁹ K).
Formed with the SI prefix 'giga-' (from Greek 'gigas', giant) applied to the kelvin base unit.
Extreme astrophysics — collapsing supernova cores reach roughly 100 GK, and Big Bang nucleosynthesis took place at about 1 GK.
The giga- prefix was adopted by the CGPM in 1960 as part of the SI.
Rankine to Gigakelvin conversion formula
The exact relationship between degrees rankine and gigakelvins:
To convert degrees rankine to gigakelvins, multiply the value in degrees rankine by 5.555556e-10. To reverse, multiply the value in gigakelvins by 1.8e+9.
Both units count upward from absolute zero, so 0 °R = 0 GK and the relationship is a pure ratio.
How to use this converter
Type a value into the calculator. The result in gigakelvins updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Gigakelvin to Rankine converter for the reverse direction.
Step-by-step: convert degrees rankine to gigakelvins
- Write down the temperature in degrees rankine (°R).
- Multiply the value in degrees rankine by 5.555556e-10.
- The result is the same temperature expressed in gigakelvins (GK).
- To reverse, multiply the value in gigakelvins by 1.8e+9 — or open the Gigakelvin to Rankine converter.
Worked examples
Example 1 — Convert 1 °R to GK:
1 × 5.555556e-10 = 5.555556e-10 GK
Example 2 — Convert 100 °R to GK:
100 × 5.555556e-10 = 5.555556e-8 GK
Rankine to Gigakelvin conversion table
Physically meaningful reference temperatures, from absolute zero to the surface of the Sun, converted from degrees rankine to gigakelvins:
| Rankine [°R] | Gigakelvin [GK] | Reference point |
|---|---|---|
| 0 | 0 | Absolute zero |
| 419.67 | 2.3315e-7 | Where Celsius and Fahrenheit coincide (−40°) |
| 459.67 | 2.553722e-7 | Zero Fahrenheit (0 °F) |
| 491.67 | 2.7315e-7 | Water freezes (0 °C / 32 °F) |
| 491.688 | 2.7316e-7 | Triple point of water |
| 509.67 | 2.8315e-7 | Cool day (10 °C / 50 °F) |
| 527.67 | 2.9315e-7 | Room temperature (20 °C / 68 °F) |
| 536.67 | 2.9815e-7 | Standard laboratory temperature (25 °C) |
| 545.67 | 3.0315e-7 | Hot day (30 °C / 86 °F) |
| 558.27 | 3.1015e-7 | Human body temperature (37 °C / 98.6 °F) |
| 563.67 | 3.1315e-7 | Heat-wave day (40 °C / 104 °F) |
| 581.67 | 3.2315e-7 | Hot tap water (50 °C / 122 °F) |
| 671.67 | 3.7315e-7 | Water boils (100 °C / 212 °F) |
| 815.67 | 4.5315e-7 | Moderate baking oven (180 °C / 356 °F) |
| 10400.4 | 5.778e-6 | Surface of the Sun (≈5,505 °C) |
Frequently asked questions
How many gigakelvins is 1 degree rankine?
How do I convert degrees rankine to gigakelvins?
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Sources & references
Conversion relationship (1 °R = 5.555556e-10 GK) 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.