For Designers
The Toolkit for Designers Who Implement Their Own Work
When you split time between design and implementation, you need tools that move as fast as you do. onHover puts color picking, contrast validation, CSS inspection, screenshot capture, and responsive viewport testing in one popup — available on any page without opening DevTools.
5 tools for the design-to-implementation workflow
Color Eyedropper
Pick any color from any site, instantly
Click any pixel on any webpage and get the HEX, RGB, and HSL value. The eyedropper keeps a palette history so you can build a color set from a reference site without copying values one by one. Useful for extracting a competitor's palette, matching a client's brand colors to a design system, or verifying that the implemented color matches the Figma spec.
WCAG Contrast Checker
Accessibility validation during implementation
Pick any two colors from the page using the eyedropper or enter HEX/RGB values manually. onHover calculates the contrast ratio and shows AA and AAA pass-fail ratings for normal text and large text side by side. Catch contrast failures at the implementation stage, before QA or an accessibility audit does.
CSS Inspector
Computed value lookups without opening DevTools
Hover over any element to see its computed font family, size, weight, line-height, letter-spacing, color, background, padding, margin, and border radius — all at once, no panel digging. Useful when you're implementing a design and want to confirm the rendered output matches the spec, or when a client site uses a font or spacing value you want to reference.
Screenshot
Full page and element capture for design review and handoff
Capture the full page (including content below the fold), the current viewport, or a specific element. Screenshots are timestamped and include the URL. Use them for design review comments, bug reports with visual context, before/after comparisons, or client handoff documentation. No browser extension toolbar visible in the capture.
Responsive Tester
Viewport checking across every breakpoint
Switch between device presets (iPhone SE, iPhone 14, iPad, Android, Desktop) or enter a custom width. The page renders at that viewport immediately — no DevTools, no resize handles, no layout shift from the inspector sidebar itself taking up screen space. Rotate between portrait and landscape. Zoom in to check dense layouts.
A typical design review pass
How these tools fit together when you\'re QA-ing your own implementation.
Open the implemented page in Chrome
Use Responsive Tester to check every major breakpoint (375px, 768px, 1280px)
Hover over type elements with the CSS Inspector — confirm font, size, weight, and spacing match the spec
Use the Color Eyedropper on key UI elements — verify HEX values match design tokens
Run the WCAG Contrast Checker on text/background pairs — confirm AA compliance
Capture a full-page screenshot for the design review thread or handoff document
Also included in onHover
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