Font Performance Checker

Paste your font CSS, find loading mistakes: faux bold, render blocks, no swap. Everything runs locally in your browser, nothing is uploaded.

About this tool

Font Performance Checker: free, fast, browser-only. Nothing you type leaves this page.

Why free, and what happens next

Tools like this one are how this desk stays findable: useful first, commercial when you are ready. When a tool surfaces a problem you would rather have fixed than diagnosed, start a project or run the cost calculator first. Everything runs client-side: your data never leaves this page.

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