JPGtoWebP
Convert JPG to WebP
Up to 3 files at once, 100 with Pro. Mixed formats are fine.
Converting JPG to WebP stores the same photograph in roughly 25 to 35 per cent less space, which on an image-heavy page is the largest saving available without changing what the page contains. Drop a folder of JPGs above: they convert on your own machine, keep their names, and come back as one ZIP.
What converting JPG to WebP actually saves
If you are here, something has probably told you to do this — a Lighthouse audit, a page speed report, a client asking why the site is slow on a phone. The advice is sound. WebP typically produces a file 25 to 35 per cent smaller than a JPG of the same visual quality, and on an image-heavy page that is the single largest saving available without changing what the page contains.
Is WebP safe to serve yet?
The support question is settled and has been for a while. Every current browser reads WebP, including Safari since 2020, so a site serving it today is not excluding anyone in practice.
Where it still trips people up is outside the browser: some desktop image viewers, older versions of Office, and the occasional upload form will not recognise the format. WebP is a format for the web, and it is worth keeping the JPG for anything a human might be sent by email.
You are compressing an already-compressed image
One thing to be clear-eyed about: converting a JPG to WebP compresses an image that has already lost detail. Your JPG discarded it when it was made, and WebP now compresses what is left. At the default quality the result is visually identical and the saving is real, but you are working from a copy.
If the original photograph still exists as a RAW file, a PNG or straight off the camera, converting that gives a better result at the same file size. In practice most people only have the JPG, and converting it is still worth doing — just do it once rather than round-tripping.
WebP can also replace your PNGs
WebP carries an alpha channel, which JPG does not. That matters less coming from a JPG, since there is no transparency to preserve, but it is why WebP can replace both JPG and PNG on a site. A logo that had to be PNG for its transparency and a photograph that had to be JPG for its size can both be WebP, which is one format to serve instead of two.
WebP or AVIF?
The honest answer is: AVIF is better, but not yet instead of. It compresses roughly 20 per cent tighter than WebP, at the cost of much slower encoding and thinner support in older software. If your setup can serve both and let the browser choose with a picture element, do that. If you are picking one format and moving on, WebP is the one that works everywhere today.
The conversion runs in your browser, which for this use is a practical benefit rather than a privacy one: you can drop a hundred images from a build folder and none of them go anywhere, so there is no upload wait and no size limit beyond your own machine. Take the results as a single ZIP.
How to convert JPG files to WebP in bulk
- Drop your JPG files onto this page — a whole folder is fine.
- Each converts in your browser, with its own progress.
- Download them individually, or take the batch as one ZIP.
JPG vs WebP: the same picture, a third lighter
| JPG | WebP | |
|---|---|---|
| Full name | JPEG Image | WebP Image |
| File extension | .jpg, .jpeg, .jpe | .webp |
| Media type | image/jpeg | image/webp |
| Compression | Lossy — file size is bought with quality | Either, depending on the setting |
- Quality
- Some quality is given up for a smaller file. At the default setting the difference is hard to see.
- Where it runs
- This conversion runs inside your browser. Your file is never uploaded, and it works with the network disconnected.
JPG to WebP: support, quality and AVIF
- Are my JPG files uploaded anywhere?
- No. This conversion runs entirely inside your browser, so the file never leaves your device. You can confirm it yourself: open the network tab of your browser's developer tools and watch that nothing is sent while the file converts.
- How much smaller is WebP than JPG?
- Around 25 to 35 per cent for the same visual quality, on a typical photograph. Less on images that were already heavily compressed — there is only so much to win back once the detail is gone.
- Do all browsers support WebP?
- Yes, for practical purposes. Every current browser has supported it for years, including Safari since 2020. The remaining gap is old software rather than old browsers — some desktop image viewers, older Office versions and a few upload forms still do not recognise it.
- Is converting a JPG to WebP lossy?
- Yes, twice over. Your JPG has already lost detail, and WebP compresses the decoded result again. At the default setting it is not visible, but converting the same image back and forth repeatedly will degrade it. Convert from the original if you still have it.
- Should I use WebP or AVIF?
- AVIF compresses better — often another 20 per cent — but encodes far more slowly and support in older software is thinner. WebP is the safe default for a site that has to work everywhere today. If you can serve both and let the browser pick, do that.
- Can I convert a whole folder at once?
- Drop as many files as you like and each converts separately, then take the lot as a single ZIP. Each one keeps its own name with the extension swapped, and nothing is uploaded, so there is no queue and no daily allowance to run out of.