Every free image converter online uploads your photos to someone's server, then caps you at 5–10 files a day so you'll buy a plan. This one runs entirely in your browser — your files never leave your device, so there's no quota to sell you. Batch-convert to PNG, JPG or WebP, resize, set quality, download as a ZIP. Reads PNG, JPG, WebP, GIF, BMP, AVIF, SVG and ICO. JFIF files are renamed, not re-encoded, so they lose nothing. Works offline once the page has loaded. No account, no watermark.
Hey Product Hunt 👋
I built this because I kept hitting the same wall: I needed to convert a folder of screenshots, and every free converter wanted me to upload them to a server I know nothing about and then told me I'd used up my 5 free files for today.
Both of those problems have the same root cause. If conversion runs on someone's server, that server costs money, so the free tier has to be small enough to make you upgrade. Move the work to the browser and both problems disappear at once: nothing is uploaded, and there's nothing to meter.
So that's what this is. Your images are decoded and re-encoded by your own browser's canvas. Pull the network cable after the page loads and it still works.
A few details I'd have wanted to know:
• JFIF is a rename, not a conversion. A .jfif file already is a JPEG, Windows just saved it with an odd extension. Most converters re-encode it and quietly cost you quality. This one verifies the JPEG start-of-image marker and hands back the original bytes under a new name. Zero re-encode, zero loss.
• Batch downloads are a real ZIP, hand-written rather than pulled from a library, with the UTF-8 flag set, otherwise Cyrillic and Latvian filenames come out as mojibake in Windows Explorer, which is exactly what happened on my first attempt.
• JPEG has no transparency, so if you convert a PNG with alpha you pick the background colour instead of getting the black rectangle other tools give you.
Honest limitation, up front: it reads PNG, JPG, WebP, GIF, BMP, AVIF, SVG and ICO, but writes only PNG, JPEG and WebP. That's a browser limitation, not a paywall — AVIF or TIFF output would mean shipping a WASM codec, and I'd rather keep the page dependency-free than add a megabyte for a rare case.
There's also a favicon generator built the same way, and I'm working out what to do next.
What I'd love to hear: which conversion do you actually reach for most often, and what makes you close a browser tool within the first ten seconds? I'd rather fix that than add formats nobody asked for.