How to glyph count vs coverage map for font selection
- Step 1Run both tools per candidate — Glyph Count → projected sizes per subset. Coverage Map → per-block coverage.
- Step 2Cross-reference — For each candidate: does the smallest subset that covers your audience hit the budget? If yes, candidate is viable. If no, candidate is too expensive for your performance target.
- Step 3Pick the winner — Among viable candidates, weigh design quality, brand fit, licence terms. Glyph Count + Coverage are objective screens; final selection adds subjective brand factors.
Frequently asked questions
What's a sensible decision matrix?+
X-axis: smallest subset that covers required languages. Y-axis: KB after that subset. Plot candidates; pick the lower-left quadrant (cheap, well-covered). Eliminate the upper-right (expensive, over-covered).
How does this scale across multiple fonts?+
Apply per font. Body, heading, and code fonts each get their own budget and coverage requirements. The matrix is per-font; the design system aggregates.
Can I automate this?+
Yes — both tools have CI scripts. Output a unified per-font report with size + coverage. Compare candidates programmatically before human review. The Coverage Map + Glyph Count combined is enough for ~90% of selection decisions.
Privacy first
Every JAD Font tool runs entirely in your browser using opentype.js and the wawoff2 WASM Brotli encoder. Your fonts never leave your device — verified by zero outbound network requests during processing.