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Color Format Converter Online

Convert color values between HEX, RGB, and HSL formats. Full support for opacity and alpha channels with live visual previews.

color swatch preview
format conversions

WCAG Color Contrast Checker

Calculate readability contrast ratios of text against backgrounds to ensure compliance with WCAG 2.1 accessibility criteria.

Contrast Ratio: 4.50:1
Normal Text
AA: PASS AAA: FAIL
Large Text
AA: PASS AAA: PASS
Preview text styling under these colors.
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Color Palette Generator

Explore matching color schemes. Click any swatch to select it as the active color.

Monochromatic Palette

Complementary Palette

Analogous Palette

Design systems and modern web browsers represent colors using several mathematical models. While monitors render pixels by blending Red, Green, and Blue light channels, designers often prefer working with parameters that represent color perception. Understanding color formats allows developers to easily manipulate themes, programmatically adjust layout contrasts, and implement transparency layers.

Core Color Models

The three primary color notations used in CSS stylesheets include:

  • HEX: A base-16 representation of color components (e.g. #RRGGBB). It is the standard format for styling and graphic software.
  • RGB: A decimal notation specifying the intensity of Red, Green, and Blue channels from 0 to 255 (e.g. rgb(255, 0, 0)).
  • HSL: Defines color using Hue (angle on the color wheel from 0 to 360), Saturation (percentage of color purity), and Lightness (percentage of brightness). HSL is ideal for adjusting color values programmatically.

Transparency and the Alpha Channel

Alpha parameters control opacity, blending background colors with overlay objects. Modern CSS specifications integrate transparency using functional wrappers (like rgba() or hsla()) or by appending 2 hexadecimal digits to a standard HEX code, creating an 8-character string where 00 is transparent and FF is fully opaque.

frequently asked questions

What is the difference between RGB and HSL? +

RGB (Red, Green, Blue) defines colors by mixing primary light sources, which matches how monitors render pixels. HSL (Hue, Saturation, Lightness) describes colors based on human perception. HSL makes it easy to create lighter/darker variations of a color by modifying the Lightness percentage.

How does the alpha channel affect color? +

The alpha channel defines the opacity of a color. A value of 1 (or 100%) represents a completely solid, opaque color. A value of 0 represents a completely transparent color, allowing objects behind it to show through.

How is transparency represented in HEX values? +

HEX values represent opacity by appending two extra hexadecimal characters at the end of the standard 6-digit code, creating an 8-character string (e.g., #FF000080 represents red at 50% opacity, where 80 is the hex equivalent of 128/255).

What are the value limits for HSL? +

Hue is represented as an angle on the color wheel from 0 to 360 degrees (where 0 is red, 120 is green, and 240 is blue). Saturation and Lightness are represented as percentages from 0% to 100%.

Are color codes case-sensitive in CSS? +

No. HEX codes and functional color notations (like rgb or hsl) are case-insensitive in HTML and CSS. Hexadecimal codes like #fff and #FFF are parsed identically by the browser.