Compress Images Without Uploading

Every image compression tool on the first page of Google works the same way: you upload your image, their server compresses it, you download the result. Your file spent time on someone else’s computer, and you have no way to verify what happened to it.

This tool is different. Drop an image below and it gets compressed right in your browser. The file never leaves your device.

Converting from PNG to JPG typically reduces file size by 5 to 10 times. Use the quality slider to control the tradeoff between size and visual fidelity. 92% (the default) is indistinguishable from the original for most photos and screenshots.

Why does the format change?

PNG is a lossless format: it preserves every pixel exactly. That fidelity comes at a cost in file size. JPG uses lossy compression, discarding visual detail that the human eye has trouble noticing, which is why the output is so much smaller.

For photos, screenshots of web pages, and most images where exact pixel accuracy doesn’t matter, JPG at 90% or above looks identical to the original. If you need to keep transparency or are compressing line art or diagrams, PNG to WebP is a better choice: WebP keeps transparency and still compresses well.

Why not just use TinyPNG or Squoosh?

TinyPNG uploads your images to their server. Squoosh (by Google) actually does run in the browser, but it’s a developer tool with an interface built for one image at a time. If you need to quickly shrink a file for an email or a web form without thinking about compression settings, the drop zone above does the job.

The difference with most “free compression” tools is simpler than it sounds: your file either leaves your computer or it doesn’t. Here, it doesn’t.

Other ways to shrink images privately

• JPG to WebP produces smaller files than JPG at the same quality. WebP is supported by all modern browsers.
• HEIC to JPG is the right path if you’re starting with iPhone photos.
• BMP to JPG gives the biggest reduction: BMP files are uncompressed and can be 10 to 50 times larger than the JPG equivalent.