Batch Image Converter

Convert multiple images to one target format at once, and download them all as a ZIP. Runs entirely in your browser.

Convert multiple images

Add several images, choose a target format, then convert them all at once.

Drag & drop images here, or click to browse
Select multiple JPG, PNG or WEBP files at once.

    Batch complete

    Files converted
    0
    Output total size
    0 KB
    Your images are processed locally in this browser tab using the Canvas API and packaged with JSZip. Nothing is uploaded to Calcooo or any server.

    How to use this tool

    1. Drag and drop several images into the box above, or click to browse and select multiple files.
    2. Choose the format you want to convert every image to — JPG, PNG or WEBP.
    3. Press Convert all & download ZIP and wait while each image is processed.
    4. Click Download batch-converted-images.zip to save every result in one file.

    FAQ

    Frequently asked questions

    Are my images uploaded anywhere?

    No. Everything happens locally in your browser using the Canvas API to convert each image, and JSZip to package the results — nothing is uploaded to a server.

    Can I convert a mix of formats in one batch?

    Yes. Upload any mix of JPG, PNG and WEBP images — they'll all be converted to the single target format you choose.

    Will converting to JPG lose transparency?

    Yes. For any images with transparency, since JPG doesn't support it — those areas are filled with white.

    What do I download?

    A single ZIP file containing every converted image, with each filename's extension updated to match the new format.