Color Picker for UI/UX Designers
Color is one of the most powerful tools in a UI/UX designer's toolkit — it establishes hierarchy, communicates states, reinforces brand, and guides user attention. But choosing colors that work well together, pass accessibility requirements, and align with brand guidelines simultaneously is a constraint-heavy problem. An online color picker that combines visual selection, format conversion, image sampling, and WCAG contrast checking removes most of the friction from this problem. This article walks through a designer-focused color workflow from initial palette creation to accessibility verification and handoff.
Starting With Your Brand Color and Building a Palette
Every UI color system starts with a brand color — a specific HEX or RGB value provided by brand guidelines, or a color you are establishing for the first time. This anchor color determines the hue of your primary palette, and all other colors should relate to it in a principled way. Step 1: Enter the brand color in the Color Picker. Whether you have a HEX code, an RGB value, or you are sampling from a logo, get the exact value into the tool first. Step 2: Build a tonal scale around it. A tonal scale provides multiple lightness variations of the same hue — from near-white at the light end to near-black at the dark end. In the color picker, take the oklch representation of your brand color and note the hue (H) and chroma (C) values. Then create 5–9 variations by stepping through the lightness (L) value while keeping H and C approximately constant. Very light and very dark shades may need their chroma reduced slightly, as very light/dark high-chroma colors can look neon or muddy. Step 3: Add a secondary or accent color. Choose a hue that is harmonious with your primary. Complementary (opposite on the color wheel, 180° away in hue), analogous (30–60° away), or triadic (120° away) relationships all produce different aesthetic results. Use the hue slider in the color picker to explore these relationships visually. Step 4: Define neutral grays. Pure grays (chroma 0) can look cold and harsh. A warm-neutral (slightly warm hue tint, chroma 0.01–0.02 in oklch) or cool-neutral (cool tint) reads as more refined in UI contexts. Define at least 5 neutral shades from near-white (lightness 0.95+) to near-black (lightness 0.15 or less). Step 5: Add semantic colors. Success (green), warning (yellow/amber), error (red), and info (blue) complete a typical semantic color set. Choose hues that are distinct from each other and from your brand primary even for color-blind users.
Accessibility Checking in the Design Process
Accessibility is not a final audit — it is a constraint that should be applied throughout the design process. Catching contrast failures early prevents expensive redesign later. Integrate contrast checking as you define each color pair, not after the design is finished. Every time you assign a text color to a background, check the pair immediately: — Body text on page background — Link colors in body text — Button label color on button background — Form label and input text on input background — Placeholder text (informational, should meet 4.5:1) — Icon colors adjacent to their backgrounds In the WikiPlus Color Picker, enter the text color in the foreground field and the background in the second field. The ratio and pass/fail for AA/AAA appears instantly. For component-level accessibility, document each verified pair in your design system: Button — label: #FFFFFF on #0011FF — ratio 6.1:1 — passes AA Button hover — label: #FFFFFF on #0009D4 — ratio 8.3:1 — passes AAA Input — text: #1A1A1A on #FFFFFF — ratio 18.1:1 — passes AAA Input — placeholder: #767676 on #FFFFFF — ratio 4.54:1 — passes AA This documentation serves two purposes: it confirms accessibility compliance during design review, and it provides developers with exact verified values they can implement directly. For color blindness: after defining the semantic color set, view the palette with a grayscale filter (available in Chromium DevTools under Rendering > Emulate vision deficiencies). If success green and error red look the same shade of gray, add an icon or text label as a secondary indicator for those states.
Sampling From UI Mockups and Screenshots
Color pickers are not only for creating palettes from scratch — they are also essential tools for maintaining consistency when working from existing designs, matching competitor UI, or aligning with a client's existing digital materials. Sampling from a client's website or app: Take a full-resolution screenshot of the relevant UI. Upload it to the WikiPlus Color Picker. Hover over the element whose color you want to capture — a button, a header background, a link color — and click to sample. This is faster and more accurate than trying to inspect the page's CSS manually. Working from Figma or Sketch mockups: Export a PNG of the frame you are working with. Upload to the color picker and sample the exact colors used in the mockup. This is useful for front-end developers who need the exact values without access to the original design file. Matching printed materials: If you have a high-resolution scan of a printed piece and need to match the digital color to what was printed, sample from the scan as a starting point. Note that CMYK-to-RGB conversion may produce slight differences, and the print color may have shifted from the original sRGB value during printing. Use the sampled value as a starting point and adjust for perceived accuracy against the physical piece. Creating a 'source of truth' library: After sampling all colors from a project's existing materials, export the values into a structured color library document. This becomes the canonical reference that prevents color drift across the project as it evolves.
Handoff: Exporting Colors for Developers
The last step in the design-to-development color workflow is handoff — providing developers with color values in the exact format they need for implementation. For most modern web projects, provide color values in three formats: 1. HEX: for compatibility with older codebases, email templates, and any tool that requires HEX 2. oklch: for use in CSS custom properties, design token files, and modern stylesheets 3. RGB: for JavaScript canvas work, SVG attributes, or backend image processing Structure your handoff as a design token file. JSON format is portable and can be consumed by style dictionary, Token Transformer, or similar build tools to generate platform-specific output: { "color": { "primary": { "500": { "value": "#0011FF", "type": "color", "description": "Primary brand blue. Use for interactive elements." } } } } Annotate each token with: — The intended use case (which UI elements it applies to) — Which background colors it is approved to appear on — The contrast ratio against those backgrounds — Whether it has been verified for WCAG AA/AAA compliance For Figma handoffs: add color styles to a shared library with full names (Primary/Blue/500 rather than just blue-500) and include the HEX and oklch values in the style description field. Developers using the Figma Dev Mode can view these values directly. A well-documented handoff reduces back-and-forth, prevents implementation errors, and creates an accountability record showing that accessibility checks were performed during design.
Frequently Asked Questions
- How do I choose a secondary color that works with my primary brand color?
- Use the hue angle in oklch or HSL to find harmonious relationships. Complementary colors are 180 degrees opposite your primary hue on the color wheel — they create high visual contrast and dynamic tension. Analogous colors are 30–60 degrees adjacent and create cohesive, monochromatic-adjacent schemes. Triadic colors are 120 degrees apart and provide variety while maintaining balance. In the Color Picker, note your primary color's hue value, then try each of these angles as secondary candidates, adjusting lightness and chroma to fit your design style. Always verify that the secondary color also passes WCAG contrast against the backgrounds it will appear on.
- What is the best way to handle color in a multi-brand design system?
- Use a two-tier token architecture. The first tier is brand tokens — specific color values unique to each brand, stored separately per brand. The second tier is semantic tokens that map to brand tokens: --color-interactive maps to the brand's primary blue. When switching brands, only the brand token layer changes; all component styles referencing semantic tokens remain untouched. This is the architecture used by large design systems serving multiple clients or white-label products. The Color Picker helps by letting you sample the exact brand color values for each brand and export them into the brand token layer.
- How many shades should I include in a color tonal scale?
- Five to nine shades is the practical range for most design systems. A 5-step scale (lightest, light, mid, dark, darkest) covers most use cases: light for backgrounds and subtle fills, mid for primary brand elements and interactive states, dark for text and high-contrast elements. A 9-step scale gives you more granularity for states (hover, active, disabled) and a wider range of subtle backgrounds. More than nine steps rarely adds value for UI design and makes the token list harder to navigate. Start with 5 and add steps only when you encounter a specific design need that cannot be met by interpolating between existing steps.