Free Online JPEG Image Compression
Offline local lossless compression — images processed on your device, no upload.
ImageTool.app's online JPEG compressor quickly reduces JPEG file size while keeping images sharp. Everything runs locally — no upload required.
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Drop image files here to compress online, losslessly
Fast processing
No server upload — images are compressed right in your browser.
Privacy first
Files stay on your device. Nothing is stored, tracked, or shared.
Download freely
Grab the result instantly.
Unlike online tools that upload your files to third-party servers, ImgZilla compresses JPEG fast and entirely locally, with virtually no quality loss. 100% local, no signup, no subscription.
Why local JPEG compression
Faster batches
Compress JPEG quickly even on an ordinary computer — no upload waits, server queues or rate limits.
Zero upload, more privacy
Files always stay local, never uploaded to any third-party server — client material and private photos stay safe.
No file size limit
Easily handle tens-of-MB shots from wedding proofs or medium-format cameras, free of the size caps online tools usually impose.
Quality stays sharp
A perceptual visual compression algorithm keeps sharp edges and only compresses flat areas aggressively — the difference is barely visible.
How to compress JPEG
Drop in a JPEG
Just drag your JPEG in — no upload.
Export
Export right after compression — no ZIP packaging, no waiting on a server.
FAQ
The before/after difference is nearly imperceptible, typically shrinking 50–80% (e.g. 4MB down to 800KB–1.2MB).
No. Compression happens entirely locally; your images never leave your device.
They're exactly the same format, just different file extensions, stemming from early Windows limits on extension length.
The online tool is great for a few images quickly; the desktop app supports unlimited batches and multi-threaded whole-folder compression.
Download ImgZilla for faster batch compression
Want faster batch compression and stronger privacy? The ImgZilla desktop app does everything locally on your Mac — just drag and drop.
- 100% local processing — images are never uploaded
- Multi-threaded batch compression, up to 90% smaller
- Originals auto-backed up to Trash, recoverable anytime
- Compare before and after with the built-in image compare tool
