Use Bulk Image Converter - free
Frequently asked questions
How many images can I convert at once?
Up to 10 images per batch. If you drop more, only the first 10 are added to the queue - convert those, clear the queue, and drop the next batch.
Can each image have a different output format?
Yes. The format and quality at the top apply to the whole batch, but every image in the queue has its own format dropdown and quality slider that override the global setting for just that file.
How do I download all the converted images at once?
After converting, use the "Download all as .zip" button to save every result in a single ZIP file, or use the Download button on each row for individual files.
Are my images uploaded to a server?
No. Decoding, resizing, and re-encoding all happen locally in your browser using the Canvas API, so your images never leave your device.