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Compress PNG Images

100% in-browser · no upload · WebP/JPG savings · batch

Compress PNG images entirely in your browser — files never leave your device, so it works offline with no upload-size cap. The biggest real savings come from re-encoding PNG to WebP (typically 50–80% smaller at the same visual quality, transparency preserved); JPG output is universal but flattens transparency, and keeping the output as PNG is lossless but only trims a few percent. Drop a whole batch, pick the quality, and see the exact size delta before you download.

Drop image files here

Multiple files allowed

    no files
    Ready.

    How to compress an image

    1. Drop one or more PNG, JPG, or WebP files.
    2. Pick the output format — WebP for the web (smallest, keeps alpha), JPG if you need universal support, PNG only if you must stay lossless.
    3. Set quality. 0.7 is a strong default for photos. Drop to 0.55 for aggressive savings; raise to 0.85+ for design assets where artefacts would show.
    4. Click Compress. The size delta (e.g. −42%) is shown next to each output so you can decide whether to keep it.

    Which format should I pick?

    Common targets

    FAQ

    Is it safe to compress images here?

    Yes — compression runs entirely in your browser with JavaScript. Your images are never uploaded to a server, so nothing can be intercepted, logged, or retained. You can even disconnect from the internet after the page loads.

    Why did my PNG barely shrink?

    The browser's PNG encoder only does a fresh deflate pass — typically 0–10% saving. For real PNG optimisation use oxipng or pngquant on the desktop, or just switch the output to WebP at quality 1.0 for near-lossless WebP that's 40–60% smaller.

    Can the output be bigger than the input?

    Yes — converting a tiny 8-colour PNG (already very efficient) to WebP can grow it. The size delta column shows when this happens; just keep the original in that case.

    Does compression strip EXIF?

    Yes. WebP and the re-encoded JPG output don't carry the source EXIF through. If you need EXIF preserved, don't compress — or use a desktop tool with explicit metadata handling.

    Will it work offline?

    Yes. The tool is plain JavaScript running in your browser — no server round-trip. After the page has loaded once, you can disconnect.