LAB to RGB Converter (CIE L*a*b* Color Space)
指导
LAB to RGB Converter
Convert CIE L*a*b* color values to RGB and HEX formats with scientific accuracy. This tool performs the full LAB to XYZ to RGB transformation pipeline using the D65 standard illuminant and proper sRGB gamma correction, with visual color preview and out-of-gamut detection.
如何使用
Enter your LAB values — L (lightness, 0-100), a (green-red axis, -128 to 127), and b (blue-yellow axis, -128 to 127). The tool instantly converts to RGB values (0-255) and HEX format with a live color preview. Switch to RGB-to-LAB mode for reverse conversion. Out-of-gamut colors are flagged when the LAB value falls outside the displayable sRGB color space.
特征
- LAB to RGB Conversion – Full LAB → XYZ → linear RGB → sRGB pipeline with D65 illuminant
- 双向 – Convert LAB to RGB or RGB to LAB with a single toggle
- 颜色预览 – Live visual swatch showing the converted color
- Out-of-Gamut Warning – Alerts when LAB values cannot be accurately displayed in sRGB
- HEX Output – Automatic HEX color code alongside RGB values
- sRGB Gamma Correction – Proper gamma curve application for accurate color rendering
- Range Validation – Input validation ensuring LAB values stay within valid ranges
- 客户端处理 – All calculations run in your browser with no server dependency
常问问题
What is the CIE L*a*b* color space?
CIE L*a*b* (CIELAB) is a color space defined by the International Commission on Illumination that describes all perceivable colors. L represents lightness (0 = black, 100 = white), a represents the green-red axis, and b represents the blue-yellow axis. Unlike RGB which is device-dependent, LAB is designed to approximate human vision, making it the standard for color science and print production.
Why do some LAB colors show as out-of-gamut?
The LAB color space is larger than the sRGB color space used by most monitors. Some LAB values describe colors that are physically real but cannot be displayed on a standard sRGB screen. When a LAB color falls outside the sRGB gamut, the RGB values would need to go below 0 or above 255, requiring clipping. The out-of-gamut warning indicates that the displayed color is an approximation of the true LAB color.
What is the D65 illuminant and why does it matter?
D65 is a standard illuminant defined by the CIE that represents average daylight with a correlated color temperature of approximately 6504K. It serves as the reference white point for sRGB and most modern displays. The choice of illuminant affects how LAB values map to XYZ coordinates during conversion — using a different illuminant like D50 (common in print) would produce different RGB results from the same LAB input.
How does LAB to RGB conversion work mathematically?
The conversion follows a two-step pipeline. First, LAB values are converted to CIE XYZ tristimulus values using the inverse of the CIELAB formulas with the D65 white point reference. Then, XYZ values are transformed to linear RGB using the sRGB color matrix, and finally a gamma correction curve (the sRGB transfer function) is applied to produce the final 0-255 RGB values. This ensures perceptually accurate color reproduction on sRGB displays.
