Most online converters work the same way. You pick a file, it goes to someone else's server, gets converted there, and comes back. For a HEIC photo or a Word doc, that's a strange trip to take.
Convertle skips it. The conversion runs in your browser, on your own device, so the file never leaves it.
Live site: convertle.help
What it converts
Images, video, audio and documents.
- Images: HEIC, JPG, PNG, WebP, AVIF, SVG, and a long list of RAW and specialist formats
- Video: MP4, MKV and more
- Audio: MP4 to MP3, for example
- Documents: Word to Markdown, for example
Drop in one file or a whole folder, pick the output format, and download everything together. Quality, size and codecs are adjustable if you care. If you don't, the defaults are fine.
There is no account and no subscription.
Why do it in the browser
Privacy, mostly. If a file never leaves your device, nobody else can store it, scan it or lose it in a breach. That matters for personal photos and client files.
It is also faster for big files, since nothing uploads and comes back down. And with no server doing the work, there is no reason to charge per conversion.
How it works
Convertle runs on WebAssembly and the browser's built-in media APIs. WebAssembly lets heavy code run at close to native speed, and the media APIs handle a lot of image, audio and video work directly. Everything from reading the file to writing the output happens inside the open tab.
Limitations
It is not finished. Big videos depend on your device's memory, so a phone will struggle with files a laptop handles fine. PDF conversion is not supported yet.
Try it ↗
Open convertle.help, drop in a file and see what happens. There is no sign-up, and nothing is uploaded.
If a format is missing or a conversion fails on your device, tell me. I would like to know which format to add next.
You can see more of my work at shayanali.dev.