How to Read Color Codes — HEX, RGB, HSL, and CMYK Explained
January 26, 2026 · 7 min read
A clear, practical guide to reading and converting HEX, RGB, HSL, HSV, and CMYK color codes.
Why color codes exist
Designers, developers, and printers all need a precise way to say "this exact shade of blue." Each format optimizes for a different use case.
HEX codes (#RRGGBB)
Six hex digits, two each for red, green, blue, 00 to FF (0 to 255 in decimal). #FF0000 is pure red, #00FF00 is pure green, #FFFFFF is white, #000000 is black.
RGB on a 0–255 scale
Same three channels, just written as decimal numbers: rgb(255, 0, 0). Easier to read at a glance, more verbose to type.
HSL — Hue, Saturation, Lightness
Hue is the color (0–360°). Saturation is how vivid (0–100%). Lightness is how bright (0% black, 100% white). Designers love it because adjusting one slider does what you'd expect.
CMYK for print
Cyan, magenta, yellow, black (key). Subtractive — you start with white paper and add ink. Always check colors look right in CMYK before sending to print, because some screen blues just don't exist in ink.
HSV / HSB
Same idea as HSL but uses Value/Brightness instead of Lightness. Most design apps (Photoshop, Figma) expose HSB pickers.
Converting between them
The math is straightforward but tedious. Our free color converter handles it instantly with a live swatch preview.
Frequently asked questions
What is #FFFFFF?
Pure white. Same as rgb(255, 255, 255).
What is RGB(0,0,0)?
Pure black. Same as #000000.
Try the tools: