How to Convert HEX to RGB (and RGB to HEX) Online Free

How HEX and RGB relate

HEX is just RGB in hexadecimal. #FF5733 splits into FF (255 red), 57 (87 green), 33 (51 blue). The conversion is lossless and two-way. HEX is popular because it's compact and CSS-friendly; RGB wins when you need to do math on components or add alpha transparency with rgba().

What the color converter gives you

• HEX 6-digit — #FF5733 — standard web color
• HEX 8-digit — #FF5733FF — adds alpha channel
• HEX 3-digit shorthand — #F53 — CSS shorthand for duplicated nibbles
• RGB — rgb(255, 87, 51) — component form
• RGBA — rgba(255, 87, 51, 0.8) — with alpha 0-1
• HSL — hsl(11, 100%, 60%) — hue, saturation, lightness; intuitive for color picking
• HSV — hsv(11, 80%, 100%) — used in design tools
• CMYK — cyan, magenta, yellow, black for print work

When to reach for HSL

HSL is the format that lets you reason about colors like a human. Same hue, darker? Drop the L. More vivid? Raise the S. Generating a color palette? Step the H by 30-60 degrees. The math is trivial in HSL and awful in HEX/RGB. For theme design systems, storing hues + separate saturation/lightness variables makes later edits dramatically easier.

The alpha channel trap

HEX traditionally doesn't have alpha. Modern CSS supports 8-digit HEX (#RRGGBBAA) but older browsers don't parse it. For compatibility, use rgba() — supported since IE9. Alpha values range 0 (transparent) to 1 (opaque) in CSS; 00-FF in HEX.

Color math: contrast, darkening, analogous colors

WCAG AA requires a contrast ratio of at least 4.5:1 between text and background. Convert both colors to RGB, compute relative luminance, take the ratio — failing that check is the most common accessibility bug on the web. For darkening a brand color for hover states, dropping HSL lightness by 8-12% gives a consistent perceived shift.

Related color tools

Need to pick a color visually rather than convert a known value? Use the color picker. For optimizing SVG icon files (including their color attributes), use SVG optimizer.