Paste CSS and check @font-face blocks for font-display, src, woff2 usage and blocking-risk patterns.
This checker is for frontend performance QA when custom fonts are added or changed. Paste CSS and review @font-face blocks before a release.
What it checks
The report lists font-family, src and font-display for each @font-face block. It flags missing font-display, missing src, block behavior, inline data URL fonts and missing woff2 sources.
Scope
The tool checks CSS text only. It does not measure real font loading, FOIT, FOUT, CLS or Core Web Vitals.