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Compress

re-encode at quality of your choice · WebP / JPG / PNG

Drop images and re-encode them at a chosen quality. WebP gives the best size / quality trade-off; JPG is universally supported; PNG re-encode is lossless but typically only saves a few percent.

Drop image files here

Multiple files allowed

    no files
    Ready.

    When to use this tool

    Use Compress when image weight matters — page-load performance, mobile bandwidth, email attachments. The output's size delta is shown in the row label so you can see what each file gained or lost.

    Step by step

    1. Drop the images.
    2. Pick the output format. WebP is best for the modern web.
    3. Set quality. Default 0.7 is roughly visually lossless on most photos.
    4. Click Compress. The size delta (e.g. −42%) appears next to each output.

    Use cases

    FAQ

    Why does PNG mode barely shrink anything?

    The browser's PNG encoder uses default compression settings. For real PNG optimisation use a desktop tool like oxipng or pngquant. Or switch the output to WebP at quality 1.0 for near-lossless WebP.

    What's the right quality?

    0.7 is a strong default. Drop to 0.55 for very aggressive savings; bump to 0.9 if compression artefacts are visible. Always preview the result before bulk-applying.

    Can the output be bigger than the input?

    Sometimes — e.g. converting a tiny 8-colour PNG (very efficient) to WebP can be larger. The size delta in the output row tells you when this happens.