Compress images
The same encoders the well-known compression services run on their servers — except here they run on your machine, so your photographs never leave it.
- Runs entirely in your browser
- Works offline
- No upload
- No sign-up
- No watermark
Loading the tool…
How it works
- Drop your images.
- Set the quality; “Squeeze harder” switches to MozJPEG / OxiPNG.
- Compress and download, individually or as a ZIP.
Why nothing is uploaded
Every operation on this page is done by code running inside your browser tab, using the same engine that renders web pages. The file is read from disk into your tab’s memory, transformed there, and written back out as a download. It is never sent anywhere — not to us, not to a third party.
Verify it yourself
- Open your browser’s developer tools (F12) and select the Network tab.
- Load your file and run the tool.
- The only requests you will see are the tool’s own code and, once cached, none at all.
Frequently asked questions
What does “squeeze harder” actually change?
For JPEG it swaps your browser’s encoder for MozJPEG, which trellis-optimises the quantisation and typically saves another 10–20% at the same visual quality. For PNG it runs OxiPNG, which is lossless: it only reorders and re-deflates the data, so the pixels come out bit-for-bit identical.
Is PNG compression lossy here?
No. OxiPNG never changes a pixel. If you need a big reduction on a photograph stored as PNG, convert it to JPG or WebP instead — that is where the real saving is.
The saving is 0%. Is it broken?
No. Some files are already optimally packed, usually because they came out of another compressor. The tool reports the honest number instead of quietly handing back a re-encoded file of the same size.
Are the images uploaded to convert them?
No. The image is decoded by your browser, redrawn on a canvas and re-encoded there. Load the page, switch your connection off and the conversion still works — that is the proof.
Is there a size or batch limit?
None that we impose. Drop a hundred files if you like; they are processed one after another with a progress bar, and the ceiling is your device’s memory.
What happens to EXIF and GPS data?
It is dropped by default, which is usually what you want before sending a photo to anyone. Tick “Keep EXIF” if you need the capture date and camera preserved in a JPEG output.