How to use this format converter
Format conversion sounds trivial until you hit the edge cases: a PNG with transparency turning into a JPEG with black edges, a HEIC file from an iPhone that a website refuses to accept, a 100 MB TIFF that an upload form silently rejects. This converter handles the three formats that actually matter for the web, and it does it without an upload queue, an account, or a daily limit.
Drop your files in, choose the target format, and hit convert. The original file is decoded by the browser's image pipeline, drawn to an off-screen canvas at its native resolution, and re-encoded in the format you picked. Dimensions are preserved exactly; if you also need to change the size, use the image resizer instead.
Converting to WebP
This is the conversion most people should be doing. WebP has been supported in Chrome, Firefox, Safari and Edge for years, and it consistently beats JPEG on file size at equivalent perceived quality. Converting a folder of JPEGs to WebP at quality 88 typically cuts total weight by roughly a third with no visible change, which translates directly into faster page loads and better Core Web Vitals scores.
WebP also carries an alpha channel, so it can replace PNGs used for logos and UI graphics. A PNG-24 logo that weighs 240 KB will often come out around 30 KB as a lossy WebP with the transparency intact.
Converting to JPEG (and the transparency trap)
JPEG has no concept of transparency. When you convert a PNG with a transparent background to JPEG, those pixels have to become something. A naive conversion leaves them black, which is why so many logos end up with an ugly dark box around them. This tool asks you for a background colour first and paints it underneath the image before encoding — set it to match the page the image will sit on, usually white.
Convert to JPEG when a system demands it: some older content management systems, some print workflows, some job application portals, and a surprising number of government upload forms still accept nothing else.
Converting to PNG
PNG output is lossless, so the quality slider disappears when you select it. Converting a JPEG to PNG does not recover any quality — the information JPEG discarded is gone forever, and PNG simply stores the already-degraded pixels without further loss, usually in a much bigger file. Convert to PNG when you need transparency in a format with universal support, when you are feeding an image into software that cannot read WebP, or when you need pixel-exact fidelity for a screenshot or diagram.
What about HEIC, AVIF, TIFF and RAW?
The converter can read anything your browser can decode natively, and it will happily convert those files to WebP, JPEG or PNG. In practice that means: Safari on Apple devices can open HEIC, so iPhone photos convert directly there; most current browsers can decode AVIF; TIFF and camera RAW formats are generally not decodable in a browser and will be rejected. If a file will not load, open it in your operating system's photo viewer, export a JPEG or PNG, and convert that.
Output is deliberately limited to the three web formats. Encoding to AVIF requires an encoder the browser does not expose to web pages, and shipping a WebAssembly encoder would add several megabytes of download to a page that is meant to be instant.
Batch conversion tips
Files are converted sequentially rather than in parallel. This is slower on a desktop with many cores, but it prevents mobile browsers from running out of memory halfway through a batch and killing the tab — a trade the tool makes deliberately in favour of reliability.
Filenames keep their base name and gain the new extension, so holiday-photo.jpg
becomes holiday-photo.webp. If you convert into the same folder as the originals,
nothing is overwritten. When you use "Download all", the browser may ask once for permission to
download multiple files; grant it and the remainder will save without further prompts.