Bulk Image Converter
Move a whole folder between JPG, PNG and WebP. Free — no account needed, and nothing is uploaded.
Drop your images here
or select them from your computer — up to 200 at a time
Supported formats: JPG, PNG, WebP, BMP, GIF or AVIF in — JPG, PNG or WebP out · max 30 MB per fileUp to 200 files · nothing is uploaded
BMP, GIF and AVIF are read and come back as JPG, PNG or WebP — a browser canvas cannot write them. Animated files are not accepted.
How to use
Add your images
Drop a folder onto the box above, or press Select images. They stay on your machine.
Choose a format
WebP for the web, PNG for lossless quality and transparency, JPG for compatibility.
Convert and download
Each image lists its old and new format. Take one, or the whole batch as a ZIP.
Transparency, and what JPG does to it
PNG and WebP can store an alpha channel — the record of which pixels are see-through. JPG cannot. There is no way to save a transparent JPG, so converting one means deciding what colour goes behind the image.
The usual failure is that nothing decides, and the transparent areas come out black — because an empty canvas is transparent black and JPG keeps the colour while dropping the transparency. This tool always fills first, with white by default, and tells you which of your images are affected before you convert. If you need the transparency kept, convert to PNG or WebP instead.
Choosing between JPG, PNG and WebP
- WebP — usually the best choice for the web. Typically 25–35% smaller than a JPG at the same visual quality, supports transparency, and is supported by every current browser.
- PNG — lossless, with transparency. The right answer for logos, screenshots and anything with sharp edges that has to stay pixel-exact. Photographs saved as PNG are usually much larger than they need to be.
- JPG — photographs, and anywhere that has to open a file without question. No transparency, and every save loses a little quality.
Why convert in the browser?
Re-encoding an image is arithmetic on pixels your computer already has. Sending a file to a server to have that done, then sending it back, is slower for a large batch, costs someone money per image, and puts your files on a machine you do not control. Doing it locally is the reason this tool has no sign-up and no usage limit.
Frequently asked questions
- Are my images uploaded anywhere?
- No. Conversion happens in your browser using the canvas API. Your images never leave your computer, which is why the tool needs no account and has no usage limit.
- What happens to transparency when I convert to JPG?
- JPG has no transparency. Converting a transparent image to JPG replaces the transparent areas with a solid colour, which is white by default and which you can change before converting. The tool marks which of your images are transparent so nothing is a surprise. Convert to PNG or WebP instead if you need the transparency kept.
- Which formats can I convert between?
- JPG, PNG and WebP in any direction, and BMP, GIF and AVIF can be read as well. Those three cannot be written back — a browser canvas encodes JPEG, PNG and WebP and nothing else — so a BMP comes out as one of the three. Animated GIFs, animated WebPs and APNGs are refused rather than accepted, because a canvas only ever sees the first frame and the animation would be silently lost.
- Why is there no quality setting for PNG?
- PNG is a lossless format — the browser encoder ignores a quality setting entirely, so showing one would be a control that does nothing. Quality applies to JPG and WebP.
- Which format should I choose?
- WebP is usually the best choice for the web: it is typically 25 to 35 per cent smaller than a JPG at the same visual quality and it supports transparency. Use PNG when you need lossless quality or sharp edges, and JPG when the file has to open anywhere at all.
Related reading
Working out a batch workflow? There is a guide to batch image processing, and if you are selling online, see Amazon’s photo requirements.