HEX, HSL, HSV, RGB Color Converter (Alpha Support)

Working with color across different platforms means constantly translating between formats. A designer hands you an HSL value, your CSS needs HEX, your JavaScript animation library expects RGB, and your image editor thinks in HSV. Rather than juggling browser tabs and mental math, this converter lets you work in whichever format you’re comfortable with and instantly see the equivalent value in every other format.

Pick a color visually using the color field and hue slider, search by name from a library of over 1,500 named colors, or type a value directly into any field. Every format updates in real time as you make changes, and the alpha slider lets you dial in transparency across all formats that support it. Click the copy icon next to any value to drop it straight onto your clipboard, ready to paste into your code, design tool, or style sheet.

Understanding Color Formats: A Complete Guide

Every color you see on a screen is ultimately a combination of light, but the way we describe that combination varies depending on the tool, the language, and the task at hand. Each color format below represents a different way of thinking about the same color — some are built for machines, others for human intuition, and most exist because a specific discipline needed a model that matches how its practitioners actually work.

HEX

HEX is the shorthand that built the web. A HEX color is a six-character string of hexadecimal digits, prefixed with a hash sign, where each pair of characters represents the intensity of red, green, and blue on a scale from 00 to FF (0 to 255 in decimal). The format originated in early HTML specifications as a compact way to define color in markup, and it remains the most widely recognized color notation in front-end development. Nearly every CSS style sheet, email template, and brand guideline document you encounter will reference colors in HEX.

Its strength is brevity. A value like #2A6F97 is easy to copy, paste, and compare at a glance. Its limitation is that the relationship between the six characters and the color you actually see is not intuitive — there is no way to look at #2A6F97 and know it is a muted steel blue without either memorizing the value or converting it.

HEXA

HEXA extends the standard HEX format by appending a fourth pair of hexadecimal digits that represents the alpha channel — the opacity of the color. A value of FF means fully opaque, 00 means fully transparent, and everything in between produces a semitransparent result. The notation #2A6F9780, for example, describes the same steel blue at roughly 50% opacity.

HEXA gained practical support with the CSS Color Level 4 specification and is now understood by all modern browsers. It is particularly useful when you need transparency in contexts where only a single color string is accepted, such as certain design tokens, SVG attributes, and Android resource files where the eight-digit format (sometimes with alpha first) has been standard for years.

HSL

HSL describes color the way most people naturally think about it: by hue, saturation, and lightness. Hue is the position on the color wheel measured in degrees from 0 to 360, where 0 is red, 120 is green, and 240 is blue. Saturation is a percentage that controls how vivid the color is — 100% is the purest version of the hue, and 0% is a completely neutral gray. Lightness is also a percentage, where 0% is black, 100% is white, and 50% gives you the fullest expression of the hue at its given saturation.

CSS adopted HSL as a first-class notation because it makes programmatic color manipulation far more intuitive than working with raw RGB channels. Need a darker version of a button color? Reduce lightness. Need a pastel palette? Lower saturation and raise lightness. Need a complementary color? Add 180 to the hue. These operations are trivial in HSL and awkward in HEX or RGB, which is why HSL has become the preferred format for design systems, theme generation, and any context where colors are derived from a base value rather than specified individually.

HSLA

HSLA is HSL with an alpha channel appended, expressed as a decimal between 0 and 1. A value of hsla(207,57%,38%,0.5) describes the same steel blue at half opacity. Every situation where HSL is useful becomes more flexible with HSLA, because transparency is a constant requirement in layered interfaces — overlays, shadows, disabled states, glassmorphism effects, and gradient stops all depend on semitransparent color.

In modern CSS, the hsl() function itself now accepts an optional alpha parameter, making the hsla() notation technically redundant but still widely used for clarity and backward compatibility.

HSV

HSV, sometimes called HSB (hue, saturation, brightness), is the color model that most visual design tools use natively. Adobe Photoshop, Illustrator, Figma, and Sketch all present their color pickers in HSV because it maps closely to how artists and designers think about mixing color. The hue component is identical to HSL — a degree on the color wheel — but saturation and the third channel work differently.

In HSV, saturation represents the distance from white. A saturation of 0% produces white (tinted by the current value), while 100% produces the most vivid version of the hue. Value (or brightness) represents the distance from black: 0% is always black, regardless of hue or saturation, and 100% gives you the brightest version of the color at its current saturation. This makes HSV particularly intuitive for the common task of picking a color and then deciding how bright or how washed-out it should be, which is exactly what you do when you click and drag within a rectangular color field — the horizontal axis is saturation and the vertical axis is value.

HSV is rarely used directly in CSS because browsers do not support it as a native color function, but it is the model behind the color picker in this tool and in virtually every visual application. When you drag the cursor across the color field above, you adjust saturation and value, while the hue slider controls the third dimension.

HSVA

HSVA adds an alpha channel to HSV, following the same 0-to-1 decimal convention used by HSLA. While HSVA has no native CSS function, it is commonly used in JavaScript-driven rendering, canvas drawing, and game engines where colors are constructed programmatically and transparency is part of the data model. If you are building an interactive visualization or a drawing application, HSVA gives you the same intuitive control as HSV with the added ability to manage opacity as part of the color value itself.

RGB

RGB is the foundational color model for any device that emits light. Every pixel on your screen is a physical cluster of red, green, and blue subpixels, and the RGB format directly controls the intensity of each one on a scale from 0 to 255. A value of rgb(42,111,151) tells the display to set red to about 16% intensity, green to about 44%, and blue to about 59%, which produces — once again — that muted steel blue.

RGB is the native language of monitors, televisions, cameras, and LED lighting. It is also the format most commonly used in programming contexts beyond the web. JavaScript canvas operations, OpenGL shaders, LED strip controllers, and image processing libraries all work in RGB because it maps directly to the hardware. When precision matters, and you need to know exactly what each channel is doing, RGB is unambiguous.

The tradeoff is the same one that makes HEX difficult to read intuitively: the three channel values do not correspond to perceptual qualities like hue or brightness. Adjusting a single channel shifts both the perceived color and its lightness simultaneously, making it poorly suited for tasks like generating color palettes or creating accessible contrast pairs.

RGBA

RGBA extends RGB with a fourth value — alpha — expressed as a decimal from 0 to 1. It is by far the most commonly used transparent color format in web development because it has been supported in CSS since the earliest days of CSS3 and is understood by every browser, preprocessor, and design tool in existence. Anywhere you need a color with transparency — box-shadow, background-color, gradient stops, SVG fills, canvas drawing — rgba() is the reliable, universally compatible choice.

Like hsla(), the modern CSS rgb() function now accepts an optional alpha parameter, but the explicit rgba() syntax remains dominant in production code because of its clarity and because developers have a decade of muscle memory behind it.

Credit to Name That Color for the nice name lookup!