About Color Temperature (Kelvin)

Convert 1000–40000K to an RGB approximation (Tanner Helland formula). Part of the DevTools Surf developer suite. Browse more tools in the Color collection.

Use Cases

• Photographers simulating white balance adjustments in editing tools
• Lighting designers previewing LED color temperatures before purchasing
• Game developers implementing dynamic time-of-day lighting systems
• Smart home engineers mapping color temperature sliders to RGB LED values

Tips

• Enter a Kelvin temperature from 1000 to 40000 to see its RGB color
• Use the output to simulate warm candlelight (1900K) or cool daylight (6500K)
• The conversion uses the Tanner Helland formula for accurate approximation

Fun Facts

• The concept of color temperature comes from heating a theoretical 'black body' radiator — the color it emits at a given temperature in Kelvin defines that color temperature.
• Standard daylight is defined as 6504K (CIE Illuminant D65), which is the reference white point used in the sRGB color space and virtually all computer monitors.
• Tanner Helland published his color temperature algorithm in 2012, fitting a curve to CIE data with less than 1% error — it's now used in hundreds of open-source projects.

FAQ

What's color temperature?

Light sources emit different colors at different temperatures. Low Kelvin (1800K) is candle-warm orange; high (10000K) is electric blue. Daylight is ~5500K.

Which formula does it use?

Tanner Helland's approximation. Widely used, accurate enough for UI design and photography. More precise but computationally expensive methods exist for scientific work.

What's the 'temperature' slider on lights and cameras?

Same concept — 2700K is 'warm white', 4000K is 'neutral', 6500K is 'daylight'. White balance corrects for the ambient color temperature.

Is this useful for color grading video?

Yes — teal-orange looks (5500K source + 3200K fill) are common. The tool gives you the RGB to use in LUTs or gradient maps.