HEX vs RGB vs HSL: What's the Difference and When to Use Each

Every color on a screen can be written three common ways — as a hex code, as RGB values, or as HSL values — and all three describe exactly the same color, just through different mathematical lenses. Understanding what each format actually represents, rather than treating them as interchangeable magic strings, makes it much easier to work with color confidently in design or code.

What HEX actually represents

A hex code is just RGB values written in base-16 instead of base-10, packed into a compact six-character string. #3498DB is the same color as RGB(52, 152, 219) — 34 in hex is 52 in decimal, 98 is 152, and DB is 219. Hex is compact and copy-paste friendly, which is exactly why it's the default format in most design tools and CSS.

What RGB actually represents

RGB describes a color as three light intensities — red, green, and blue — each from 0 to 255, mixed together the way a screen's individual pixels actually combine light to produce color. It's the most direct representation of how a display physically produces the color you see, which is why it's the format most closely tied to how screens work at a hardware level.

What HSL actually represents

HSL describes a color by hue (its position on a color wheel, 0–360 degrees), saturation (how intense or muted it is, 0–100%), and lightness (how close to black or white it is, 0–100%). Unlike RGB, HSL maps much more closely to how people naturally think and talk about color — "a slightly darker, less saturated blue" translates directly to adjusting lightness and saturation, which isn't nearly as intuitive to do by eye in RGB.

When to reach for each one

• HEX — the most common choice for storing and sharing a specific color value, especially in CSS and design files, purely because of its compactness.
• RGB — useful when working directly with pixel data, image processing, or anywhere the underlying light-mixing model matters.
• HSL — the most useful format when you need to adjust a color intuitively — making something lighter, more muted, or shifting its hue while keeping everything else the same.

They're all just different views of the same color

It's worth internalizing that none of these formats is more "correct" than the others — they're three different coordinate systems describing the identical underlying color, the same way a location can be described by street address, latitude/longitude, or what3words. Converting between them, which the tool on this page does instantly, never changes the actual color; it only changes which numbers are used to describe it.

A quick way to spot-check a conversion

If a tool's converted output looks obviously wrong — a color you know is a muted blue-gray showing up as a vivid, fully saturated hue — it's worth double-checking that the right format was selected before pasting a value in, since accidentally pasting an RGB string into a field expecting HSL, for instance, produces a nonsensical result rather than an error message in many tools.