RGB to HSV (HSB) Converter

HSV — also called HSB (hue, saturation, brightness) — is the model behind most color pickers, including Photoshop, Figma and Procreate: pick a hue on the wheel, then move inside a square where right means more saturated and up means brighter. This converter turns RGB, HEX or CMYK into HSV and back, and also gives the 8-bit values OpenCV uses (hue 0–179, saturation and value 0–255), which is handy for color thresholding in image-processing code.

How to use this tool

1. Choose RGB/HEX → HSV, CMYK → HSV or HSV → RGB/HEX.
2. Enter the color: a HEX code or rgb(), four CMYK percentages, or hue, saturation and value.
3. Read the HSV values, the OpenCV scaling or the HEX/RGB result.
4. Use the swatch to see where the color sits in the saturation/value square.

Formula

V = max(R′, G′, B′) · S = (max − min) ÷ max · H = 60° × sector formula (as in HSL)

R′, G′, B′ are channels ÷ 255. Back from HSV: with i = ⌊H ÷ 60⌋ and f the fraction, p = V(1 − S), q = V(1 − S·f), t = V(1 − S(1 − f)); each sector picks a different order of V, t, p, q. OpenCV halves the hue so it fits in a byte and works in fixed-point integers, which this page reproduces exactly.

Example

#FF6347 has max 1 and min 0.2784, so V = 100%, S = (1 − 0.2784) ÷ 1 = 72.2% and H = 9.1° — hsv(9.1, 72.2%, 100%). In OpenCV that is H 5, S 184, V 255. Going back, HSV(210°, 66.7%, 60%) gives V = 153, p = 51, q = 102 and the sector (p, q, V) = rgb(51, 102, 153) = #336699.