Font Tools: Kerning, Ligatures, and AI Suggestions
After publishing a font through the SLF Tracer or Handwriting Capture, the Font Tools page lets you refine it further. You can add pair kerning (custom spacing between specific letter pairs), create ligatures (combined strokes for character sequences), and get AI-powered suggestions for style tags, potential ligature pairs, and glyphs that would benefit from node cleanup. Font Tools is available to Pro and Enterprise subscribers who own the font.
Opening Font Tools for one of your fonts
Go to your Creator Dashboard and find the font you want to refine. Click the "Font tools" link in the font row. The Font Tools page loads your font data and opens on the Kerning tab. The page has three tabs: Kerning, Alternates, and the AI tab (shown with a sparkle icon).
Pair kerning — tightening specific letter combinations
Kerning adjusts the spacing between specific letter pairs that would otherwise look awkward. The classic example is "AV" — the diagonal strokes leave a visible gap at standard spacing that looks wrong. In the Kerning tab, the two-glyph preview shows the current spacing between any pair you enter. Type two characters into the pair field (e.g., "AV") and use the slider to adjust the kern value — negative values tighten the spacing, positive values add space. Click Save Pair to store it. You can also run Auto-kern on a single pair or on the entire font — the auto-kern algorithm measures the visual gap between the rightmost path point of the first glyph and the leftmost of the second and suggests a correction value. Review the auto-kern suggestions before accepting them, especially for script fonts where the natural flow may already be correct.
Ligatures — combining character sequences into a single stroke
A ligature replaces a sequence of characters with a single combined glyph. In a single-line font, a well-designed ligature means the machine draws two adjacent letters as one continuous stroke rather than lifting the pen between them. Common candidates are letter pairs that naturally connect in handwriting, such as "fi", "fl", "th", "ct", or custom pairs specific to your font style. In the Ligatures tab, enter the character sequence (e.g., "fi"), paste the SVG path data for the combined glyph, and save. When a user types "fi" in the Studio with ligatures enabled, the combined stroke is used automatically.
AI tab — three types of suggestions
The AI tab sends anonymised font metadata to an AI model and returns three categories of suggestions. Tag suggestions: the AI analyses your glyph shapes and metrics and recommends 2–5 style tags from the Pathhaus taxonomy (script, sans, geometric, etc.) that best describe your font — useful if you are unsure how to categorise it. Ligature suggestions: the AI looks at your character set and existing ligatures and suggests pairs it believes would benefit from combined strokes, with a brief reason for each suggestion. Node cleanup hints: the AI lists up to 10 glyphs with high node counts and suggests which ones to prioritise for cleanup, ranked by impact on export file size and machine performance. All suggestions are advisory — you review them and decide which to act on. None are applied automatically.
When kerning and ligatures appear in downloads
Kerning pairs and ligatures added via Font Tools are included in the SLF JSON v2 file when you download your font or when a buyer downloads a purchased font. When the font is exported as an OTF file, kerning pairs are written to the font kern table, so they take effect automatically in LightBurn, Inkscape, and any application that respects OpenType kerning. Ligature substitution in OTF format (GSUB table) is a planned future improvement — at present, ligatures are available in Pathhaus Studio but require manual selection in third-party applications.
Publishing updates after using Font Tools
Font Tools edits save directly to your font record in the database — there is no separate publish step for kerning and ligature changes. Any future download of your font by buyers will include the updated kerning pairs. If you want the font to also appear in your own Studio with the updated kerning, reload the Studio font picker after making changes.
Try it in Pathhaus Studio
Free to start — optimize and export your first font file in under 5 minutes.