Inspect every kerning pair in the kern and GPOS tables. See which letter pairs adjust and by how many font units. Catch missing pairs and unintended kerning.
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We extract pairs from the legacy kern table and modern GPOS lookups
Sort by absolute kerning value and export as JSON for design QA
0 bytes uploaded. Kerning Pair Auditor runs entirely in your browser using opentype.js and the File API. Your fonts never leave your device.
This tool requires the Pro plan or higher.
Most pairs sit between -50 and +20 font units (FUnits). Negative values pull glyphs together (AV, To, Wa). Positive values are rare except for slab serifs and monospaced fonts.
Modern variable fonts often pack kerning into compact GPOS class lookups instead of explicit pairs. Older opentype.js versions may not enumerate them — try with the newest font you have.
Yes. We read pair-pos and chained-class lookups from GPOS table entries. Single-pos adjustments (rare) are not enumerated.
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