UD5 Toolkit
Relative Luminance Calculator - Online WCAG Metrics
Enter a hex color and get its relative luminance per WCAG definition. Understand why this matters for contrast.
Tag: Color Tools - Picker & Converter
61+ toolsLEGO Color Chart & Hex Reference – Online BrickLink Colors
Browse all official LEGO colors with names, years, and hex codes. Sort by hue. Perfect for builders.
Color Image to ASCII Art - Online True Color Converter
Convert any image into colored ASCII art using divs with background colors. Creates a stunning text‑based replica. View & copy HTML.
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 Inversion Calculator - Online Exact Opposite Hue
Get the exact RGB inversion (negative) of any color. Useful for dark mode theming and high‑contrast accessibility checks.
Pigment Mixing Simulator - Online Color Blending Tool
Mix two or more colors using subtractive (CMYK‑like) blending. See what happens when you combine real paints. Brush effect canvas.
CIELAB to RGB Converter - Online Bring Color Back
Enter L*a*b* values and see the corresponding RGB and hex color. Useful for advanced color manipulation.
Random Color Naming Challenge - Online Eye Test
See a random color and type its name. Score based on accuracy. Fun for designers. Local.
3D RGB Color Cube - Online Interactive Space
Explore the RGB color space as a rotatable 3D cube. Pick a color directly from the volume. Drag to rotate. Canvas 3D.
Virtual Flashlight - Online Color & Strobe Screen
Turn your browser screen into a full‑color flashlight or strobe. Adjust brightness and color. Simple utility.
Material Design 3 Color Generator - Online Dynamic Tonal Palettes
Pick a source color and generate a complete M3 tonal palette with light/dark schemes. Export as CSS custom properties.
Image Hue Shifter - Online Change Colors Easily
Rotate the hue of any image globally. Turn a red car blue instantly. Download the result. Works entirely in the browser.
Color to Pitch Synaesthesia - Online Hear a Hex Code
Enter a hex color and hear a tone mapped to its hue. Explore the connection between color and sound. Fun perceptual experiment.
Paint Color Visualizer – Online Test Wall Colors on Sample Rooms
Simulate paint colors on a pre-loaded room photo by adjusting hue, saturation. Find your perfect shade before buying. Local canvas.
HSV Color Picker - Online Traditional Hue Wheel
Classic HSV color wheel with sliders. See hex, RGB, and HSL equivalents. Intuitive for artists. No server interaction.
Smoothie Recipe by Color - Online Get Green or Pink
Want a green smoothie? Pick a color and get a simple healthy recipe. Detox, protein, or fruit.
CMYK Color Preview - Online See Print vs Screen
Preview how a CMYK value will look on screen (approximate). Compare with its RGB equivalent. Pre‑press check.
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.
Image Color Histogram - Online RGB Channel Graph
Upload an image and see its RGB and luminance histograms. Understand exposure and color distribution. Photographer tool.
Rabbit Color Genetics Calculator – Online Predict Kit Colors
Select parent colors and genotypes to predict possible offspring coat colors. Based on simple Mendelian genetics for common breeds.
Cocktail Recipe by Color - Online Pick Your Hue
Select a color and see which cocktails match it roughly. Blue for Blue Lagoon, red for Negroni. Fun bar guide.
Mood Color Journal - Online Track Days with Hues
Pick a color for each day's mood and see a month‑at‑a‑glance heatmap. Data stored locally. A private emotional log.
Color to OKLCH Converter - Online Perceptually Uniform
Convert hex, RGB, or HSL into the modern OKLCH color space. See the preview and copy CSS oklch() value. 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.
CSS Gradient Generator - Online Color Gradient Creator
Visually create beautiful linear and radial gradients. Get the CSS code instantly. Copy the code or export as image. Perfect for web designers.
Random Color Flash - Online Meditation & Focus Light
Full‑screen random colour changes at a slow pace. Use it as a dynamic background for meditation or focus.
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.
HEX to HSL Converter - Online Color Code to Hue Saturation Lightness
Translate HEX colors to HSL values and adjust lightness and saturation visually. Great for creating color variations in CSS design systems.
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.
HWB Color Picker - Online Whiteness & Blackness Model
Pick colors using the HWB (Hue‑Whiteness‑Blackness) model. Get the CSS hwb() function code. Simpler than HSL for some.
Hue Rotation Calculator - Online Shift CSS Filter Value
Enter original and target color to compute the exact CSS hue‑rotate(deg) filter needed. For precise icon and image tinting.
Tint & Shade Generator - Online Lighter & Darker Colors
Generate tints (add white) and shades (add black) for any base hex color. Copy values for design systems. Instant local generation.
HEX to RGB Converter - Online Color Code Translator
Quickly convert HEX color codes to RGB values and vice versa. See the color preview. Indispensable for web developers and graphic designers.
Hex Color Guessing Game - Online Guess the Hex Code
See a color swatch and guess its hex code. Get scored on accuracy. Improve your color intuition. Fun for designers.
HDR Color Preview - Online See Wide Gamut Colors
Test if your display supports HDR colors by rendering a gradient in Rec.2020 space. See what you're missing. Canvas based.
Sepia to Color Restorer - Online Approximate Original
Apply a tint remover that guesses the original colors from a sepia photo. Not perfect, but fun. All in canvas.
CSS Color Converter All-in-One: Hex, RGB, HSL, OKLCH
Enter color in any CSS format and see all other representations. Live preview. Swatch history.
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.
Online Color Replacer – Pick & Swap Hue in Image
Select a color in an image and change it to another hue. Canvas‑based, local processing.
Play Dough Recipe with Color Mixer – Online Non‑Toxic
Classic cooked play dough recipe with interactive color mixing. Safe ingredients. Print instructions.
Color Scale Generator - Online Create Monochromatic Stops
Generate a range of tints and shades from a single hex color. Ideal for data visualization, UI design systems, and Tailwind custom palette creation. Local tool.
Soft Proofing Simulator - Online Simulate Print Colors
Assign an ICC profile to an image and simulate how it would look on another device. For accurate color workflows. Local.
Auto White Balance - Online Fix Color Casts
Automatically restore natural colors to a photo by removing color casts. Gray world algorithm. One‑click fix. Canvas.
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.
HSL to RGB Converter - Online Precise Translation
Enter HSL values and get the exact RGB representation. Also shows hex. For fine‑tuning design tokens. Client‑side.
RGB to HSL Converter - Online Color Space Translator
Input RGB values and see the HSL equivalent with a color preview. Understand lightness and saturation. Local.
Color to Tailwind Class Converter - Online Map Hex to closest
Enter any hex color and find the nearest Tailwind CSS color class. Also shows the Tailwind palette shade.
Chromatic Adaptation Demo - Online See Color Under Different Lights
Simulate how a palette looks under daylight, tungsten, or fluorescent light. Understand metamerism. For accurate color work.
OKLCH Color Picker & Converter - Online Perceptive Color
Select colors in the OKLCH space with lightness, chroma, and hue. Convert to hex, RGB, and CSS oklch(). Perceptually uniform gradients.
Color Readability Tester - Online Visual Contrast Meter
Paste body text and test different font/background combos. See an actual passage rendered, not just a ratio. True feel for legibility.
EyeDropper API - Online Pick Any Screen Color
Use the EyeDropper API to sample a color from anywhere on your screen. Click, select, and copy the hex. No extensions needed.
HSL to HEX Converter - Online Hue Saturation Lightness to Hex
Convert HSL and HSLA color specifications back to standard HEX codes. Useful when extracting colors from CSS preprocessors. Instant client-side conversion.
CSS HWB Color Generator - Online Whiteness/Blackness Picker
Interactively create colors in HWB space and get the CSS hwb() function. Simplifies tint/shade workflows. Live preview.
RGBA to CIELAB Converter - Online Full Color Translation
Convert RGBA colors to CIELAB and other advanced color spaces. For fine‑tuning design tokens. Client‑side math.
Hex Color Darken/Lighten - Online Shade & Tint Calculator
Input a hex color and adjust its lightness by a percentage. Get tristimulus shades for CSS. Quick and visual.
Color Personality Test – Online Fun What Hue Are You?
Answer a few questions and get a playful color-based personality result. For entertainment only.
PDF Color vs Black & White Detector – Online Page Analysis
Upload a PDF and quickly see which pages contain color and which are pure black & white. Helps optimize printing.
Urine Color Hydration Tester – Are You Drinking Enough?
Match your urine color to a chart ranging from clear to dark amber. Get a simple assessment of your hydration status and how much to drink.
Color Pattern Memory Challenge – Recall the Correct Order
A sequence of colors flashes briefly; repeat it correctly. Levels increase in length to progressively challenge your short‑term memory.
Rabbit Color Genetics Calculator – Predict Kit Colors
Select the genotypes of the buck and doe to see the probability of each coat color in the litter. For common breeds like Holland Lops and Rex.