Convert images between formats
Drop a folder’s worth of images, choose the output format and quality, and download them one by one or as a ZIP. Resizing, rotation and greyscale are in the same panel, so one pass does everything.
- Runs entirely in your browser
- Works offline
- No upload
- No sign-up
- No watermark
Loading the tool…
How it works
- Drop your images (any mix of formats).
- Choose the output format, quality and, if you want, a new size.
- Convert and download individually or as a ZIP.
Why nothing is uploaded
Every operation on this page is done by code running inside your browser tab, using the same engine that renders web pages. The file is read from disk into your tab’s memory, transformed there, and written back out as a download. It is never sent anywhere — not to us, not to a third party.
Verify it yourself
- Open your browser’s developer tools (F12) and select the Network tab.
- Load your file and run the tool.
- The only requests you will see fetch the tool’s own code — and, for a few heavy tools, their open-source engine from a public CDN — plus one small page-view ping to loreatec.jp (page address and title, nothing more). None of them carry your file.
Frequently asked questions
Which format should I pick?
JPG for photographs you will send or print. PNG when you need transparency or crisp screenshots. WebP is 25–35% smaller than JPG at the same quality and works in every current browser. AVIF is smaller still and good for websites, but slower to convert, and not every older program can open it.
Are the images uploaded to convert them?
No. Your browser opens the image, redraws it and saves it in the new format, all on your device. Load the page, switch your connection off and the conversion still works — that is the proof.
Is there a size or batch limit?
None that we impose. Drop a hundred files if you like; they are processed one after another with a progress bar, and the only limit is your device’s memory.
What happens to the hidden photo data (EXIF, GPS location)?
It is removed by default, which is usually what you want before sending a photo to anyone. Tick “Keep EXIF” if you need the date and camera details kept in a JPEG output.