Optimize & Print
Compress PNG
Shrink PNG files losslessly with Oxipng (the Rust optimiser behind Squoosh) — right in your browser. Pixels stay identical; only wasted bytes go.
Your files never leave your device — conversion runs locally in your browser.
To compress PNG files, drop them above — Oxipng, the Rust optimiser behind Squoosh, re-evaluates each file's filters and compression right in your browser, never uploading anything. Pixels stay bit-for-bit identical; only wasted bytes go, typically 15-60% of the file. Pick a higher effort level for tighter results when time allows.
Honest limits
- PNG files only, and lossless only — pixels are never altered.
- Max-compression effort is noticeably slower on large images.
Need more than a browser can do? Desktop browsers go further than phones — and Media Moana converts at scale on hosted infrastructure.
How it works
Drop your files
Drag PNG files into the drop zone, click to browse, or paste from the clipboard. Whole folders work too.
Convert locally
Each file is decoded and re-encoded to PNG right in your browser — no upload, no queue. Adjust quality or size first if you like.
Download
Save converted files one by one, or download the whole batch as a ZIP. Originals stay untouched on your device.
About the formats
PNG — Portable Network Graphics
PNG is a lossless image format with full alpha transparency, supported everywhere since the late 1990s. It compresses graphics, screenshots, logos and text crisply with zero quality loss, making it the standard choice when you need pixel-perfect output or a transparent background. For photographs PNG files are larger than JPEG, but nothing is ever thrown away.
Frequently asked questions
Is this safe? Do my photos get uploaded?
No upload happens — ever. Optimising PNG runs entirely inside your browser using WebAssembly. Your files never leave your device, nothing is stored on any server, and the tool even keeps working if you go offline after the page loads. That's also why there are no file size limits, no queues and no sign-up.
Can I convert multiple PNG files at once?
Yes — drop in as many files as you like. Because conversion happens on your own computer instead of a server, there is no per-file fee, no daily cap and no waiting in line. Files are processed one after another, and you can download each result as it finishes or grab the whole batch as a single ZIP.
How does lossless PNG compression work?
PNG files contain compressed pixel data plus structural choices (filters, colour type, bit depth) that most exporters pick suboptimally. Oxipng re-evaluates those choices and re-compresses the data stream harder. The decoded image is bit-for-bit identical — only the encoding is smarter. Typical savings run 15–60% depending on the source.
Should I compress my PNG or convert it to WebP instead?
Stay PNG when the destination requires it (app stores, print portals, many CMS fields) or when you need a guaranteed pixel-perfect file — that's what this tool optimises. Switch to WebP or AVIF when you control the destination and want the smallest possible web images; the PNG to WebP tool next door handles that.
Is there a file size or quantity limit?
There is no hard limit. Server-based converters cap uploads because your files consume their bandwidth and CPU; here optimising PNG files happens on your machine, so the only practical limit is your device's memory. Desktop browsers comfortably handle very large files and big batches.