UD5 Toolkit
RGB to CIELAB Converter - Online Perceptual Color Space
Convert RGB and hex colors to CIELAB L*a*b* values. Understand perceptual lightness and chromaticity. All local math.
RGBA to CIELAB Converter - Online Full Color Translation
RGBA to CIELAB Converter
Convert RGBA (Red, Green, Blue, Alpha) colors to the perceptually uniform CIELAB color space. Get L*, a*, b* and alpha values instantly.
Input RGBA Values
R
G
B
A
CIELAB Output
L* (Lightness)
--
a* (Green–Red)
--
b* (Blue–Yellow)
--
Alpha
--
About CIELAB Color Space
The CIELAB color space (also known as CIE L*a*b*) was designed to be perceptually uniform. A change of the same amount in a color value should produce a change of about the same visual importance. L* represents lightness (0 = black, 100 = white), a* represents the green–red component (negative values toward green, positive toward red), and b* represents the blue–yellow component (negative toward blue, positive toward yellow).
Our converter takes standard sRGB values (including an optional alpha channel) and transforms them into CIELAB using the D65 reference white. The alpha value is passed through unchanged for full transparency control in design workflows.
Frequently Asked Questions
RGB is a device-dependent color model based on light emission (red, green, blue). CIELAB is a device-independent, perceptually uniform color space. In CIELAB, the numerical distance between two colors closely matches human perception of color difference, making it ideal for color grading, quality control, and scientific applications.
No. Alpha (opacity) is not part of the colorimetric conversion. The tool extracts the RGB components, converts them to CIELAB, and then reports alpha separately. This way you can keep full transparency information for compositing while still accessing precise color measurements.
We use the standard sRGB linearization, followed by conversion to CIE XYZ with D65 white point and then the standard CIE XYZ to CIELAB transformation. This follows the same mathematics used in professional color management systems, providing results accurate to several decimal places.
CIELAB is widely used in industries like print, textiles, paint, and digital imaging for color matching, color difference calculation (ΔE), and defining color tolerances. It separates lightness from chromatic channels, making adjustments more intuitive.
This converter expects numeric RGBA inputs. If you have a hex color, simply convert it to decimal RGB first (many online tools can do that). We plan to add direct hex input in a future update.
Color to CIELAB Converter - Online Perceptual Space
Convert hex or RGB to CIELAB L*a*b* values. Understand perceptual lightness and color opponents. Local math.
Color Distance ΔE Calculator - Online Perceptual Difference
Enter two hex colors and compute the CIE76, CIE94, and CIEDE2000 color difference. Understand how humans perceive color similarity.
Color Guessing Game - Online RGB to Color Challenge
Given an RGB value, pick the matching color square. Multiple difficulty levels. Improve your color perception. Fun for designers.
Image Color Extractor - Online Palette from Picture
Upload an image and extract its dominant colors or full color palette. Download as a CSS snippet or color swatch. Entirely client-side, your images stay private.
Paint Mixing Color Wheel – Online Predict Mixed Hue
Select two paint colors and see approximate mixed result. Visual blending for artists.
Webcam Color Detector - Online Live Hue Picker
Point your camera at an object and see the dominant color in real time. Click to copy the hex. Fun tool for designers.
Image Color Picker From URL - Online Remote Picture Analyzer
Enter the URL of any online image and extract its dominant colors or pick colors with a magnifier. No upload, cross‑origin friendly.
Extract Perceptual Palette - Online LAB Quantization
Extract a color palette from an image using CIELAB k‑means quantization. Results are perceptually more accurate than RGB methods.
Color Contrast Ratio Tester - Online WCAG AA/AAA Check
Enter foreground and background colors to instantly see the contrast ratio and pass/fail for AA and AAA. Simple and fast.
Extract Color Palette from Image URL - Online Without Upload
Enter an image URL to extract a 5-color dominant palette. Avoids uploading files. Uses canvas to read remote image pixels. Fast and privacy-oriented.
Relative Color Syntax Visualizer - Online Adjust Lightness/Chroma
Start from a base color and use `oklch(from color l c h)` to create lighter or darker variants. Copy the code.
Image Saturation Adjuster - Online Color Pop Editor
Increase or decrease the color saturation of your photo with a slider. Preview instantly. Download the edited image. Canvas‑based.
Image Color Palette from URL - Online Remote Photo Analysis
Enter an image URL and extract its dominant color palette. No download needed. Fast visual analysis.
Extract Colors from Image URL - Online Palette Generator
Paste a direct link to an image and get its 5 dominant colors with hex codes. No upload, uses canvas with CORS proxy.
OKLCH Color Explorer - Online Perceptually Uniform Space
Browse the OKLCH color space with sliders for lightness, chroma, and hue. See the CSS oklch() code. Modern and accessible.
Image Format Converter - Online PNG to JPEG & More
Convert images between popular formats like PNG, JPEG, WEBP, and BMP. No quality loss on conversion when using lossless formats. Private and fast.
Gradient Color Blindness Simulator - Online Test Palettes
Upload a gradient or enter a palette and simulate how it appears with different types of color vision deficiency. Ensure inclusive data visualization.
Color Scheme from Image - Online Extract Palette
Upload any picture and instantly get a 5‑color palette. Useful for UI design themes. Canvas‑based extraction.
Polymer Clay Color Mixer – Online Predict Shade Result
Select two or more clay colors and visually approximate the mixed result. Helps plan canes and blends.
Dominant Color Detector - Online Find Main Hue
Upload an image and instantly see its most dominant color as a hex swatch. Uses color quantization. Local.
GIF Optimizer - Online Reduce Size with Color Quantizer
Reduce GIF file size by lowering color count and removing duplicate frames. See side‑by‑side preview. All local.
Image Color Blindness Simulator - Upload & See
Upload any image and view it as a person with deuteranopia, protanopia, or tritanopia would. Promote inclusive design.
Accessible Color Pair Grid - Online WCAG Matrix for Vision Deficiencies
Enter foreground and background colors and see a matrix of how each pair works for normal, protanopia, deuteranopia, and tritanopia.
Live Page Color Blindness Check – Online Enter URL
Enter a website URL and apply a protanopia/deuteranopia/tritanopia filter. Test full page accessibility.
PNG to JPG Converter - Online Add White Background
Convert transparent PNGs to solid JPGs by filling the background with white or any color. Fast and local.
Interactive Color Wheel - Online Learn Color Theory
An interactive color wheel that teaches primary, secondary, tertiary colors, and harmonies. Pick and mix like a pro.
Image to Pixel HTML Table - Online Giant Pixel Art
Downscale an image to a grid of colored `<td>` cells. Create a huge HTML pixel art. Copy the code.
Pixel Art Color Picker - Online Palette for Spriters
A dedicated color picker with common retro gaming palettes (NES, Gameboy). Pick and copy hex codes. For pixel art creators.
Color Swatch Image Generator - Online PNG Palette
Enter hex codes and download a PNG swatch image with color names. Useful for design spec documents. Built via canvas.