Web Font Subset Generator – Reduce Font File to Only Used Glyphs

Font subsetting is the process of creating a reduced version of a font file that contains only the glyphs (characters) you actually need. This dramatically reduces file size — often by 70–95% — which leads to faster page loads, improved SEO rankings, and better user experience. It's especially valuable for web fonts where every kilobyte impacts Core Web Vitals scores.

This tool supports TTF (TrueType), OTF (OpenType), WOFF, and WOFF2 font formats for input. The output is generated in the same format as the input. For best compatibility across all browsers, we recommend using TTF or OTF as your source file. WOFF2 input is decompressed and processed, then output as TTF.

The easiest way is to paste your website's text content into the text area — the tool automatically extracts all unique characters. You can also use preset character sets (Basic Latin, numbers, punctuation, etc.) for common use cases. For multilingual sites, include characters from all languages your content uses. Pro tip: don't forget spaces, punctuation marks, and special characters like @, #, or ©.

Yes! The subset font retains the same format and encoding as the original. It remains a valid, standards-compliant font file. All modern browsers (Chrome, Firefox, Safari, Edge) will render it correctly. The only difference is that characters not included in the subset will display as fallback font characters (usually a rectangle or the browser's default glyph).

Basic ligatures (like fi, fl, ff) are preserved if their component characters are included in your selected set. For advanced OpenType features (stylistic alternates, swashes, small caps), the subsetting process focuses on the primary glyph mapping. If you need specific OpenType feature glyphs, manually include the characters that trigger them. For full feature preservation, consider using professional font tools.

This tool processes fonts up to 25MB in your browser. For very large fonts (like full CJK character sets with 20,000+ glyphs), processing may take a few seconds. The subsetting happens entirely client-side — your font file never leaves your device, ensuring complete privacy.

Absolutely! Paste text from all languages you need to support, and the tool will extract every unique character. This is perfect for multilingual websites. For CJK (Chinese, Japanese, Korean) fonts especially, subsetting can reduce file size from 10MB+ to just a few hundred KB by keeping only the characters you actually use.