About picture-zip

A free, privacy-first image compressor that runs entirely in your browser.

Why picture-zip?

Most online image tools upload your files to a server, cap you at 20 images, and bury the tool under ads. picture-zip is different: every byte is processed locally in your browser using WebAssembly. Your images never leave your device.

What it does

  • Batch compress and convert JPEG, PNG, WebP, AVIF and GIF
  • Compress to an exact target file size (e.g. ≤ 100 KB)
  • Preserve transparency when converting PNG to WebP
  • Download everything as a ZIP in one click
  • Works in Chinese and English, with more coming

How it works

picture-zip uses the same open-source codecs that power Google's Squoosh (MozJPEG, OxiPNG, libwebp, libavif), compiled to WebAssembly and run inside Web Workers so your UI never freezes.