Convert MP4 to MOV and MOV to MP4 — without re-encoding.
MP4 and MOV are the same family of container, so Vidly just repackages your video: the streams are copied bit-for-bit into the other container. No quality loss, no long encode — it finishes at close to file-copy speed. A small, quiet desktop utility. Free, forever.
Why it's lossless and fast
Most "converters" decode every frame and encode it again — slow, and it degrades quality. Vidly doesn't. MP4 and MOV both descend from the QuickTime / ISO BMFF container format, so switching between them is a remux: only the container changes, the audio and video streams are copied untouched.
What actually happens
Vidly runs one ffmpeg command with stream copy — no filters, no encoder. The result is byte-identical audio/video inside a new box, so the picture and sound are exactly what you started with. A multi-gigabyte clip typically finishes in seconds, because it's limited by disk speed, not CPU.
Small tool, thoughtfully made
Built as a native desktop app — no Electron, no browser, no account. Just the one job, done well.
True lossless remux
Audio and video are copied, never re-encoded. Quality stays exactly as it was — every time.
Near file-copy speed
Because there's no encoding, a gigabyte-scale clip is done in seconds, not minutes.
Batch queue
Drop a pile of files, each with its own progress bar. Run them together and cancel any one of them.
Drag & drop
Drop files or a whole folder onto the window. Output paths are derived automatically.
Faststart for MP4
MP4 output moves the index to the front, so players and browsers can start instantly.
Quiet and native
A tiny Rust app with a calm, single-accent interface. No ads, no telemetry, no upsell.
Free, open source, MIT
Vidly is open-source software under the MIT license. Read the code, build it yourself, file an issue, or send a pull request — everything lives on GitHub. There's no license key, no trial, no account. It's simply free.
License: MIT · Source: github.com/indmak/vidly · Built with Rust + iced
Download
Vidly is distributed through GitHub Releases — builds for Windows, macOS and Linux, each with its own notes. (It isn't downloaded from this website.)
GitHub Releases
Grab the latest build for your platform. Portable and installer options are listed with each release, along with the changelog.
Open GitHub Releases →A Microsoft Store listing is coming. This button is reserved and will link to the Store page once it's live. Until then, use GitHub Releases above.
Microsoft Store — coming soonQuestions, answered
Is Vidly really free?
Yes. Vidly is free and open source under the MIT license. There's no purchase, no subscription, no license key and no account — download it and use it.
Will converting lose quality?
No. MP4 ⇄ MOV conversion here is a remux: the video and audio streams are copied bit-for-bit into the new container, so the quality is identical to the source.
Why is it so fast?
Because nothing is re-encoded. The work is essentially a fast copy with a new header, so speed is limited by your disk rather than your CPU.
Do I need to install FFmpeg?
Vidly uses FFmpeg as its engine. Depending on the build, FFmpeg is either bundled or detected on your system; if it's missing, the app tells you clearly instead of failing silently.
Which platforms are supported?
Windows, macOS and Linux. Builds for each are published on GitHub Releases.
A converted file won't play in QuickTime — is that a bug?
Occasionally a codec (for example AV1 or VP9) can be stored in a MOV container but not played by Apple's QuickTime Player. The conversion itself is correct — it's a player/codec limitation, not a broken file.
Where do I download it?
From GitHub Releases. The project page is at github.com/indmak/vidly. It isn't hosted on this website.