Convert
Turn JPG and PNG into WebP, and Photoshop or Illustrator files into PNG or JPG. Batch-friendly, and nothing leaves your browser.
How Convert works
JPG & PNG → WebP
Lossless, resized, or squeezed to fit a file size. Encoded with libwebp, right in your browser.
PSD & AI → PNG/JPG
Uses the Photoshop file's flattened image, and renders every Illustrator artboard.
Never uploaded
Every file is processed on your device. Several files download as one ZIP.
Frequently asked questions
How do I convert JPG or PNG to WebP?
Drop your files into Convert, choose Lossless, Resize or Fit size, and press Convert & download. One file downloads directly; several download together as a ZIP.
Should I use lossless or lossy WebP?
Lossless keeps every pixel and suits graphics, screenshots and PNGs. For photos, Resize or Fit size usually gives a much smaller file. A lossless WebP made from a JPG is often larger than the JPG, because it preserves the JPG's compression artifacts exactly.
How does “Fit size” work?
You set a target such as 200 KB. SynthOff tries quality levels to find the highest that fits under the limit, and only shrinks the image's dimensions if even the lowest quality is too large.
Can I convert a PSD to PNG without Photoshop?
Yes. SynthOff uses the flattened image that Photoshop stores inside the file. Files saved with “Maximize Compatibility” turned off may not contain one; re-save with it on.
Can I convert an Illustrator AI file to PNG or JPG?
Yes, if it was saved with “Create PDF Compatible File” turned on (Illustrator's default). Each artboard becomes its own image at 1×, 2× or 4× size, with a transparent background for PNG.
Are my files uploaded?
No. Every file is processed inside your browser tab. SynthOff has no upload endpoint, and its security policy blocks connections to any other server, so your images never leave your device.