About Technical Color Formats
Beyond the familiar HEX and RGB formats, color science uses dozens of specialized representations designed for different technical domains. Professional workflows in photography, video production, scientific visualization, color management, and advanced CSS all require access to formats like OKLCH, Lab, XYZ, and HSV. This tool converts any color into all of them simultaneously, making it the go-to reference for technical color work.
OKLCH is the newest CSS color space, added in CSS Color Level 4. It represents colors in terms of Lightness, Chroma, and Hue in a perceptually uniform way — meaning a change of 10 units looks the same size regardless of the hue. This makes OKLCH ideal for generating accessible color scales programmatically. Lab (CIELAB) is the international standard for color measurement used by industries from print to automotive finishes.
XYZ is the device-independent master color space that connects all others — every color space conversion passes through XYZ. HSV (Hue-Saturation-Value) is the color model used by Photoshop and most professional creative software. Linear RGB removes gamma correction to expose the raw light values, needed for shader programming and machine learning pipelines.
Frequently Asked Questions
What is OKLCH and why is it better than HSL? +
OKLCH (Oklab Lightness-Chroma-Hue) is a perceptually uniform color space designed to match how human vision actually perceives color differences. In HSL, two colors with the same "lightness" value can look drastically different in perceived brightness — for example, yellow at L=50% looks much brighter than blue at L=50%. OKLCH fixes this by ensuring equal L changes produce equal perceived brightness changes regardless of hue. This makes it far more reliable for generating accessible, harmonious color scales in CSS, design systems, and data visualization.
What is CIE Lab (CIELAB) used for? +
CIELAB (L*a*b*) is the international standard for device-independent color measurement, defined by the International Commission on Illumination (CIE) in 1976. It is used in printing, paint manufacturing, automotive finishes, textile dyeing, food quality control, and any industry that needs to communicate exact colors between different devices and materials. The L* axis measures lightness, a* measures green-red, and b* measures blue-yellow. Delta-E (ΔE) — the standard measure of color difference — is calculated in Lab space. When you import a PMS or pantone color into a design file, the Lab value is the source of truth.
What is CIE XYZ? +
CIE XYZ is the foundational device-independent color space from which all other modern color spaces are derived. It was created in 1931 based on studies of human color perception and maps color to three virtual primaries (X, Y, Z) that span all visible wavelengths. Y corresponds to luminance (brightness). All ICC color profiles and color management system transformations ultimately pass through XYZ. It's used in shader programming, color management pipelines, ICC profile creation, and any work that requires absolute color specification independent of any display.
What is the difference between HSV and HSL? +
Both HSV (Hue-Saturation-Value) and HSL (Hue-Saturation-Lightness) represent color using hue and saturation, but differ in how they handle brightness. In HSL, maximum lightness (100%) always produces white regardless of saturation. In HSV, maximum value (100%) at full saturation produces the pure, vivid hue. This makes HSV more intuitive for selecting saturated colors, which is why Adobe Photoshop, Illustrator, and most creative tools use HSV for their color pickers. HSL is more common in CSS because it's easier to reason about for programmatic lightness adjustments.
What is linear RGB and when is it used? +
Standard RGB values (sRGB) include gamma correction — a non-linear encoding applied so that equal steps in the stored value produce equal perceived brightness steps on a typical monitor. Linear RGB removes this gamma and represents the actual light energy, where values are proportional to the physical light intensity. Linear RGB is required for physically accurate lighting calculations in 3D rendering, GPU shader programming, HDR pipelines, and image compositing. When you blend two colors additively in a linear space the result is physically correct; blending in sRGB space produces a slightly too-dark midpoint.
What CSS color functions use OKLCH? +
Modern CSS supports oklch() directly: color: oklch(0.65 0.15 25); — where the three values are lightness (0–1), chroma (0–0.4), and hue (0°–360°). All major browsers support oklch() as of 2023. It enables color() function for wide-gamut displays (P3, Rec2020) and is the recommended format for new CSS color design systems. The color-mix() function in CSS also works in OKLCH space for perceptually accurate blending: color-mix(in oklch, blue, red).
What is a CSS named color? +
CSS named colors are 148 colors with human-readable names defined in the CSS Color Level 4 specification. Examples include "coral", "steelblue", "goldenrod", "rebeccapurple". They map to exact hex values — for instance, "tomato" = #FF6347. The tool shows which named color is nearest to your input, which is useful for documentation, code readability, and testing. Not all colors have a named equivalent — the nearest match is calculated by color distance in RGB space.
What is the color() function in CSS? +
The CSS color() function allows specifying colors in predefined color spaces beyond sRGB, including display-p3 (Apple's wide-gamut display), a98-rgb (Adobe RGB), prophoto-rgb, and rec2020. Example: color(display-p3 0.93 0.46 0.34). This enables richer, more vibrant colors on wide-gamut displays like modern iPhone and MacBook Pro screens. Colors specified in display-p3 contain approximately 35% more visible colors than sRGB. The browser will gracefully fall back to the nearest sRGB equivalent on non-wide-gamut displays.
