How to inspect every opentype feature in a font
- Step 1Drop your font — TTF, OTF, WOFF, or WOFF2. The Inspector parses GSUB and GPOS tables.
- Step 2Read the feature list — Each row: tag, human label, presence in GSUB/GPOS, CSS snippet. Common output: kern, liga, calt for almost every font; smcp, ss01–ss20, swsh for display fonts.
- Step 3Enable in CSS — Copy the snippets you want: font-feature-settings: 'smcp' 1; for small caps. Combine multiple: font-feature-settings: 'smcp' 1, 'ss01' 1;.
Frequently asked questions
Which features are most useful?+
kern (always on by default), liga (standard ligatures, default on), calt (contextual alternates, default on for proper Arabic shaping etc.), smcp (small caps), ss01–ss20 (stylistic sets), swsh (swashes), tnum (tabular numerals), onum (old-style numerals).
Can I see what each stylistic set does?+
Not from the Inspector alone — stylistic sets are font-defined and have no semantic meaning across fonts. ss01 in Inter is different from ss01 in Roboto. Foundry docs are the only authoritative source for what each set does.
How do features differ from font-variation-settings?+
Features are discrete substitutions (small caps, ligatures, tabular figures). Variation settings are continuous axes (weight, width, slant). They're orthogonal — a font can have both. font-feature-settings: 'smcp' 1; and font-variation-settings: 'wght' 700; coexist.
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.