10 Free Online Color Tools Every Designer Must Bookmark in 2025

Design tools come and go, but a handful of free, browser-based color utilities have quietly become essential to professional designers worldwide. You do not need an expensive subscription to access world-class color tooling. You just need to know where to look. Here are ten tools worth bookmarking right now.

Before we dive in — if you are still learning the fundamentals of how color systems work, start with our Ultimate Guide to Building a Color Palette from Scratch. These tools will make a lot more sense once you understand the framework behind them.

1. Coolors (coolors.co)

Coolors is probably the most widely used color palette generator on the internet, and for good reason. Hit the spacebar and it generates a five-color palette in milliseconds. Lock any colors you love, and it randomizes the rest. You can start from a photo, start from a hex code, or start from nothing. The export options cover HEX, RGB, HSL, PDF, and image formats. The free tier is genuinely excellent. If you only bookmark one tool on this list, make it this one.

Best for: Quick palette exploration and client presentations.

2. Adobe Color (color.adobe.com)

Adobe Color has been around for years under various names, and it remains one of the most powerful free color tools available. The harmony rules panel — complementary, triadic, analogous, split-complementary, square — lets you explore color relationships visually on an interactive wheel. The accessibility checker is particularly valuable: it tests your foreground and background colors against WCAG 2.1 AA and AAA standards instantly. You can read more about why those standards matter in our article on WCAG Color Contrast and Why Your Website Needs It.

Best for: Color theory exploration and accessibility checking.

3. Paletton (paletton.com)

Paletton is built around color theory in a way few tools are. You choose a base hue, select a scheme type, and it generates a full palette with tints and shades while showing you a real-time preview on a sample webpage layout. It is old-school in appearance but deeply useful in practice. The example previews — buttons, text, headers, backgrounds — help you see how a palette actually behaves in a UI context.

Best for: Understanding how a palette performs in real layouts.

4. Khroma (khroma.co)

Khroma uses AI to learn your color preferences. You spend a few minutes selecting colors you love from a curated set, and the system builds a personalized model that generates two-color combinations it predicts you will like. Thousands of pairings are generated instantly, each shown in typography, gradient, image, and gradient contexts. It is surprisingly accurate and endlessly explorable.

Best for: Creative exploration when you feel stuck or uninspired.

5. Contrast Checker by WebAIM (webaim.org/resources/contrastchecker)

This is the industry standard for quick WCAG contrast checking. Input two colors, and it instantly tells you the contrast ratio and whether you pass AA or AAA for normal and large text. No frills. No distractions. Just the answer you need. Every designer building for the web should have this open in a pinned tab. It pairs perfectly with our deeper guide on color contrast requirements.

Best for: Fast accessibility compliance checks during UI work.

6. CSS Gradient (cssgradient.io)

CSS Gradient is a visual gradient builder that outputs clean, cross-browser CSS code. You can build linear, radial, and conic gradients with a drag-and-drop interface, adjust angles and color stops, and copy the resulting CSS in one click. The gallery section shows trending gradient styles used by real websites, which is great for inspiration. We have written a full tutorial on this topic — Creating Stunning CSS Gradients: A Step-by-Step Guide — if you want to go deeper.

Best for: Building and exporting CSS gradients without writing code manually.

7. Color Hunt (colorhunt.co)

Color Hunt is a community-curated gallery of four-color palettes. Every day, designers submit palettes and the community votes on them. The result is a constantly refreshed feed of trending combinations. You can filter by mood tags — pastel, dark, warm, neon, vintage — and click any palette to copy individual hex codes. It is great for spotting what is trending in design right now, and connects well to our piece on The Hottest Web Color Trends Designers Are Using Right Now.

Best for: Finding curated palette inspiration fast.

8. Realtime Colors (realtimecolors.com)

This is one of the newer tools on the list and one of the most impressive. Realtime Colors lets you apply a full five-color palette — background, foreground, primary, secondary, accent — to a live website preview in real time. Swap any color and the entire page updates instantly. It takes the guesswork out of how a palette actually behaves at scale. Export options include CSS variables, which slots directly into modern web projects.

Best for: Testing palette combinations in a realistic page context.

9. Huemint (huemint.com)

Huemint applies machine learning to generate palettes that feel coherent and intentional. You set how many colors you need, pick a style bias (pastel, bright, dark), and it generates complete palettes shown on realistic UI mockups — websites, logos, social media graphics. The adjacent colors algorithm ensures generated colors have meaningful relationships rather than random combinations.

Best for: Generating brand-ready palettes with AI assistance.

10. Lch Color Picker (css.land/lch)

For designers and developers working with modern CSS color spaces, this tool is invaluable. LCH (Lightness, Chroma, Hue) is a perceptually uniform color model — meaning when you increase the lightness value, the color actually looks lighter to human eyes, unlike HSL. As browsers expand support for LCH and OKLCH, understanding these color formats becomes increasingly important. Our article on HEX vs RGB vs HSL: Which Format to Use covers the landscape of color formats in detail.

Best for: Advanced developers working with modern CSS color spaces.

The Takeaway

You do not need to use all ten of these tools. Find three or four that match your workflow and use them consistently. A contrast checker, a palette generator, and a gradient builder will cover the vast majority of what you need on a daily basis. The rest are there when a specific challenge calls for them.

The best designers are not the ones with the most tools. They are the ones who know their tools deeply.