Reduce web font file size by creating a font subset. Keep only the characters you need, with support for custom characters, Unicode ranges, and a live preview. Boost your site performance and Core Web Vitals.
Smaller font files download faster, improving the LCP (Largest Contentful Paint) metric, which is crucial for site performance.
Users see your text content quicker, reducing wait times, which can lower bounce rates and increase satisfaction.
Page speed is a key ranking factor for search engines like Google. Optimizing fonts is a powerful way to improve your Core Web Vitals score.
This tool runs entirely in your browser. We do not upload, store, or analyze your files. Everything you process stays on your device.
Font Subsetter is most useful when it sits inside a small repeatable workflow: prepare the source, make the change, then check the output before sharing it.
Use Font Subsetter for this job: Reduce web font file size by creating a font subset. Keep only the characters you need, with support for custom characters, Unicode ranges, and a live preview. Boost your site performance and Core Web Vitals. It keeps the task in the browser without moving the work into a heavier desktop app.
Preview the result, compare it with the original, and repeat the settings until the file is ready for a real project.
For adjacent tasks, stay inside the text & developer tools collection instead of opening another service.
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Yes, it is 100% secure. All font processing happens locally in your browser. Your font file is never uploaded to our servers, ensuring your data remains private.
This can happen with very small or highly-optimized original fonts. The tool rebuilds the font file from scratch, and this new structure can sometimes be less compact than the original. If this occurs, it means your font is already very efficient, and you should continue using the original file.
For modern web development, both are excellent starting points. After subsetting, it is best practice to convert the resulting font to the `.woff2` format for maximum compression.
You must adhere to the license of the original font you upload. Subsetting a font does not change its license. Ensure you have the rights to modify and use the font for your purposes.