About CompressLocal
CompressLocal is a free, privacy-first file compression tool built for people who care about their data. Unlike most online compression services, we never receive your files. Every compression operation runs entirely in your browser using standard web APIs.
Our Philosophy
The best privacy tool is one that literally cannot access your data. CompressLocal is designed on this principle: because we process everything locally, there's no server that could leak, store, or analyze your files — even if we wanted to.
How It Works
Modern browsers expose powerful APIs — Canvas API, FileReader API, and WebAssembly — that allow sophisticated image and document processing without any server involvement. CompressLocal uses these APIs to compress your files at native speed, directly on your device.
- Image compression uses the Canvas API to re-encode images at your chosen quality level.
- PDF compression uses pdf-lib, a pure JavaScript PDF library, to re-serialize your PDF with object stream compression.
- All processing happens in your browser tab. When you close the tab, any loaded file data is gone.