Color temperature Kelvin to RGB
Enter a temperature such as 2700 K for warm bulbs or 6500 K for daylight to get an approximate display color.
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Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.
How to use it
- Enter color temperature.
- The result appears straight away and updates as you edit.
- Copy the result, or copy a link that keeps the same values to share it.
How it is calculated
Tanner Helland approximation: T = K ÷ 100. If T ≤ 66: R = 255, G = 99.4708 ln(T) − 161.1196; else R = 329.6987 (T − 60)^−0.1332, G = 288.1222 (T − 60)^−0.0755. B = 255 if T ≥ 66, 0 if T ≤ 19, else 138.5177 ln(T − 10) − 305.0448.
Example
Inputs: Color temperature = 6,500 K. Result: HEX code: #FFFEFA; Red R: 255; Green G: 254.
Limits and caveats
- This is a curve fit to black-body color, not a colorimetric calculation; channels can be off by a few steps.
- A real bulb looks different depending on its type and your screen calibration.
Questions about this tool
What do 2700K and 6500K on bulbs mean?
2700K is warm yellowish light like classic bulbs; 6500K is cool white close to daylight.
Why are higher numbers bluer?
As a black body gets hotter its glow shifts from red to white and then toward blue.
How accurate is this?
It uses the well-known Tanner Helland approximation, fine for display and graphics, not for professional lighting measurements.