Subset TTF fonts — locally, in your browser
Web fonts carry thousands of glyphs you never use. Subsetting keeps exactly the characters you need — the same HarfBuzz engine behind professional tooling, running in your browser.
What this tool does
Point the subsetter at the text your site actually renders (or keep all glyphs) and it rebuilds the font around those characters. Name records you care about are preserved, and the output is a valid TrueType font your sites can serve immediately.
Font licensing is honoured strictly: fonts flagged restricted (fsType) or no-subsetting are refused with a clear message instead of being processed blindly.
How to subset a TTF font without uploading it
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Add the file. Drop your .ttf into the home-page tool.
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Subset. Give the text to keep (or keep all glyphs) — HarfBuzz rebuilds the font locally.
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Download locally. The smaller font is saved straight back to your disk.
Supported operations
This list is generated from CompressKit's capability registry — only implemented and tested operations appear here.
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Inspect file details
Font metadata: family, glyph count, embedding permissions.
Frequently asked questions
- Is my font uploaded anywhere?
- No. Subsetting runs on HarfBuzz compiled to WebAssembly inside your browser’s worker. The font never leaves your device.
- Will subsetting break my font’s licence?
- The tool reads the font’s own embedding-permission bits and refuses restricted or no-subsetting fonts outright. It is designed to respect the licence, not evade it.
- How much smaller will the font be?
- Latin UI fonts commonly drop by half or more when subset to a page’s characters. The result shows the honest measured size — including when the win is small.
Ready to try it?
The TTF font compressor tool runs on this site with no upload step — your file is processed by your own browser and saved back to your device.
Open the TTF font compressor tool