CIELAB Color Calculator

CIELAB Color Calculator

Professional color science tool for converting between RGB, HEX, CIELAB (L*a*b*), and XYZ color spaces with precise mathematical accuracy. Essential for color quality control, Delta E calculations, and achieving perceptual color uniformity across different devices and media with D65 illuminant standard.

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Quick Presets
Common colors for quick conversion
Input
Enter color values in RGB, CIELAB, or HEX format
How it works: Converts between RGB, CIELAB, and XYZ color spaces using the sRGB to XYZ matrix with D65 illuminant. CIELAB is perceptually uniform — equal numerical differences correspond to equal visual differences.

Complete Guide: CIELAB Color Calculator

Everything you need to know about using this tool effectively

What is CIELAB Color Calculator?

The CIELAB Color Calculator converts colors between the CIELAB (L*a*b*) color space and standard RGB and XYZ spaces. It also calculates the Delta E color difference between two LAB values. CIELAB is a perceptually uniform color space used in color science, print, and design. All processing happens in the browser.

This tool implements the standard CIE color space conversion formulas. It converts RGB to XYZ using the sRGB transfer function and D65 illuminant, then XYZ to LAB using the reference white point. The reverse conversions are also supported. Delta E (CIE76) is calculated as the Euclidean distance between two LAB points.

Key Features
Converts RGB to LAB and LAB to RGB
Converts XYZ to LAB and LAB to XYZ
Calculates Delta E (CIE76) between two LAB values
Uses D65 illuminant and sRGB color space
Shows L*, a*, b* components individually
Copy values to clipboard
Runs in the browser with no uploads
Six decimal place precision
Common Use Cases
When and why you might need this tool

Measuring color difference

Calculate the Delta E between two colors to determine how perceptibly different they are.

Print color matching

Convert RGB screen colors to LAB for accurate print color matching.

Color science research

Work with LAB values for experiments requiring a perceptually uniform color space.

Quality control in manufacturing

Compare production color samples against a target using Delta E values.

How to Use This Tool
Step-by-step guide to get the best results
1

Enter a color

Input an RGB hex code or LAB values.

2

Convert

The tool converts between color spaces and shows all representations.

3

Compare two colors

Enter two LAB values to calculate the Delta E difference.

4

Copy values

Copy the LAB, RGB, or XYZ values you need.

Pro Tips
1

Delta E below 1 is imperceptible. 1-2 is barely noticeable. Above 3 is clearly visible.

2

L* represents lightness (0=black, 100=white). a* is green-red axis. b* is blue-yellow axis.

3

LAB is perceptually uniform: equal numerical distances represent equal perceived differences.

4

Use LAB when you need to measure color differences, not just represent colors.

Frequently Asked Questions
What is CIELAB?

CIELAB (L*a*b*) is a color space designed to be perceptually uniform. Equal distances in LAB space correspond to roughly equal perceived color differences. It is widely used in color science and print.

What is Delta E?

Delta E is a single number representing the total color difference between two colors in LAB space. A Delta E below 1 is generally imperceptible to the human eye.

Is my data sent to a server?

No. All conversion happens in your browser. Nothing is transmitted.

What illuminant is used?

The tool uses the D65 illuminant, which represents average daylight and is the standard for sRGB.

Can I convert hex to LAB?

Yes. Enter a hex color code and the tool converts it through RGB to XYZ to LAB.