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Compress PNG Images

live size preview · 1:1 artefact compare · no upload · 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. Drag the quality slider. The line under it shows the real encoded size of the first file at that setting — actual bytes, not an estimate — and the two panes beside it show the same crop at 200% before and after, so you can see artefacts appear before you commit to a batch.
    4. When the size and the pixels both look right, click Compress. The size delta (e.g. −42%) is shown next to each output too.

    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.

    Part of: Put a photo on a web page

    Resize first. Compressing before you scale down spends quality on pixels you are about to throw away.

    1. 1 Resize Scale to the width the layout actually renders at
    2. 2 Compress Pick the quality, watching the size delta
    3. 3 PNG to WebP The format that carries alpha and still halves the bytes
    4. 4 Remove metadata Strip the camera and location data before it ships
    5. 5 File size Confirm what you are about to upload weighs

    All 28 step-by-step workflows

    Part of: Make a profile picture

    Square the crop before you round it — a circle mask on a 4:3 image cuts off the chin.

    1. 1 Crop to ratio Square it, keeping the face centred
    2. 2 Circle crop Round it off with real transparent corners
    3. 3 Resize Down to the size the site stores (often 400px)
    4. 4 Compress Under whatever the upload limit is

    All 28 step-by-step workflows