Image tools · convert
A website wants its photos light. This door converts one JPG to a WebP, the format modern browsers read and the one that usually weighs least, here in your browser. It is a fresh lossy write over an already-lossy picture, so the quality setting matters and the result line prints the bytes before and after. A whole folder at once is the batch convert page; the reverse trip is WebP to JPG.
For one JPG headed for a website: a blog photo, a product shot, a page image that has to load fast.
Pick a JPG
Set the quality
Download the WebP
Drop a JPG on the tray, or click to pick one
JPG in · WebP out · it stays on this device
The weight changes, and the dimensions do not. WebP writes the same picture in fewer bytes than JPG at a like quality; the exact saving depends on the photo, and the result line prints yours. One caution, printed before you run: this is a second lossy write over the JPG, so keep the quality high.
Higher keeps more detail and more bytes. 90 is a good all-round setting.
Pick a JPG to begin.
The JPG is decoded by the open-source jSquash codecs and written as a WebP at your quality, the same engine the batch convert page runs. The first run loads the image program (about 2 MB, one time only). The download is how we protect your privacy: the program comes to your device and does the work there, so your file never leaves it.
WebP is for screens and browsers. Older editors, some office programs and print queues still refuse it, so it is the wrong format to send into the unknown; the WebP to JPG door exists for exactly that trip back. And the saving is not magic on every photo: a small or already-tightly-written JPG may barely shrink, and the result line shows the number either way.
It depends on the photo, but the direction is reliable. Measured with this same engine on the batch convert page: the test photo as WebP at quality 80 came out at 251,730 bytes, against 435,388 bytes from the biggest converter on the same file. Your result line prints your own before and after.
It is a second lossy write over a picture that was already written lossily once, so yes, a little, and the page will not hide it. Keep the quality high (90 is the starting setting) and keep the JPG if it is your master copy.
On websites, where every modern browser reads it and smaller photos mean faster pages. It is the wrong choice for sending to older programs or print queues that may refuse it; for those, the JPG you already have is the right file.
Nowhere. It is decoded, re-encoded and offered back to you inside this page. Nothing is uploaded.