Who Built This?
CompactJPG is built and maintained by Chuan, an independent developer focused on creating simple, privacy-first web tools that solve real problems. You can find him on GitHub.
This project grew out of a simple frustration: most online image compressors either upload your files to a server (privacy risk), show intrusive ads, or require registration. There had to be a better way.
Why CompactJPG Exists
Modern web browsers are powerful enough to handle image compression locally using WebAssembly. MozJPEG, libwebp, and OxiPNG — the same battle-tested compression libraries used by professional tools — can run directly in your browser. There is no technical reason your files need to leave your device.
CompactJPG was built on this principle: privacy as a technical guarantee, not a policy promise. When the code runs entirely in your browser, there is nothing to trust — your files simply never go anywhere.
Our Approach
- Zero server uploads — All image processing uses browser-based WebAssembly. Your files stay on your device, period.
- No tracking, no ads analytics — We use minimal, privacy-respecting analytics only to understand if the tool is useful. No cross-site tracking, no ad networks.
- Metadata stripping by default — EXIF, GPS coordinates, camera details, and timestamps are automatically removed from compressed images.
- Always free — No pro tiers, no file limits, no watermarks. If it is useful, it should be free.
Technical Foundation
CompactJPG uses industry-standard compression libraries compiled to WebAssembly:
- MozJPEG for JPEG compression (the encoder used by Mozilla Firefox)
- libwebp for WebP compression (Google reference encoder)
- OxiPNG for PNG optimization
These run alongside custom JavaScript for format detection, color quantization (Median Cut algorithm for PNG8 conversion), and batch processing coordination — all within your browser sandboxed environment.
Contact
For questions, bug reports, or feedback, reach out at privacy@compactjpg.com. Bug reports with sample images (if you are comfortable sharing) are especially helpful.
If you would like to follow the development or contribute, the project is open source and available on GitHub.