Compress an image to under 20 KB

Forms often want a photo or signature under 20 KB. Fizzdoc keeps the picture as large and sharp as it can, lowers the JPG quality only as far as needed, and never uploads your photo.

Runs on your device · 0 bytes uploaded

    How to compress Image to 20 KB

    1. Add one or more images (JPG, PNG, WebP or a phone photo).
    2. Check the limit (20 KB is filled in; change it if your form asks for a different size).
    3. Click “Compress images” and download the result.

    Private by design — and you can check

    Your files are never uploaded, because there is nowhere to upload them to.

    Frequently asked questions

    Are my files uploaded anywhere?

    No. Fizzdoc does the work inside your browser tab, using open-source engines compiled to WebAssembly and JavaScript. Your file is read from your device, processed locally, and the result is saved straight back to your device. You can check this yourself: open your browser’s developer tools, go to the Network tab, and run a job — no request carries your file.

    How does it keep the photo clear?

    Like messaging apps, it first keeps the photo about 1600 pixels on its longest side and lowers the JPG quality step by step, never below 50% while the photo is 1000 pixels or larger. Only if that is still too big does it make the picture smaller.

    What if my form needs an exact pixel size too?

    Use Resize Image first to set the width and height the form asks for, then compress the result here.

    Is Fizzdoc free?

    Yes. There is no sign-up, no watermark and no daily limit. Fizzdoc is open source under the Apache-2.0 license.

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    Free and open source. Forever.

    No ads, no accounts, no servers looking at your files. If Fizzdoc saved you time, a star on GitHub helps more people find it.

    Star Fizzdoc on GitHub9