The problem
At IMPACT! Brand Communications, converting images to WebP kept coming up. WebP files are smaller than JPEGs and PNGs, which makes web pages load faster.
The quick fix is a free online converter. Almost all of them work by uploading your files to their server. For agency work, those files are often client assets, and sending them to an unknown third party is not a good habit.
What I built
Image to WebP is a converter that runs entirely in the browser. Drag in JPEG or PNG files, convert them in a batch, and download the results together as a zip.
There is no upload step, because there is nowhere to upload to. The files never leave your machine.
How it works
The conversion uses the browser’s own canvas. Each image is drawn onto a canvas, and canvas.toBlob() exports it as image/webp. The result is wrapped back into a file with a .webp extension, ready to download.
For batches, JSZip bundles the converted files into a single zip, also in the browser. The app has no API and no backend, only a static page, so keeping files private is not a policy. It is simply how the tool is built.