Font Checker — Font & CSS Inspector

About

Identify any font on any website — in one hover.

Font Checker is a fast, lightweight typography inspector for developers, designers, and anyone curious about web type. Click the icon (or press Alt+Shift+F), hover any text, and instantly see exactly how it's styled. Click to pin a full breakdown.

Features
- Instant hover tooltip — detected font, weight, size, and color follow your cursor
- Pinned detail panel — click any text for the full breakdown
- Smart font detection — finds the actually rendered font from the CSS stack, not just the first name listed
- Font source detection — Google Fonts, Adobe Fonts / Typekit, Fontshare, CDNFonts, Cloud.typography, Monotype, Bunny Fonts, and self-hosted @font-face
- WCAG contrast grading — live ratio with AA / AAA pass/fail
- Size conversion — px, rem, and em side by side
- One-click copy — CSS, Tailwind classes, color (HEX), or full details
- Smart + Advanced modes — selector, dimensions, text stats, font shorthand, stretch, variant, shadow, opacity, FontFace status
- Shortcuts — Alt+Shift+F toggle · Esc exit · M more · C copy CSS · T copy Tailwind

Runs entirely on your device inside an isolated Shadow DOM, so it never clashes with the page. No accounts, no servers, no data collection.