How to use Video converter
- Choose a video: MP4, WebM, MOV or MKV.
- Pick MP4 (H.264) or WebM (VP9), and a quality: keep original, high, balanced or smaller file.
- Select Convert. Your browser's own video encoder does the work on your device.
- Play the result to check it, then download it.
Convert a video without sending it anywhere
Videos come in more formats than most apps accept. An iPhone records MOV, a screen recorder saves WebM, a website wants MP4, and a messaging app refuses the one you have. This converter changes a video from one format to another inside your browser: MP4 with H.264, which plays almost everywhere, or WebM with VP9, which is smaller and suits the web.
Nothing is uploaded. Online converters usually send your whole video to their servers, which takes a long time for a big file and leaves a copy of a private recording somewhere you can't see. Here the work is done by your browser's own video encoder, the same one it uses for video calls, so the file never leaves your device.
Choosing a quality
Keep original is the fastest choice. When the video and sound already suit the new format, as with most iPhone MOV files going to MP4, they are copied across untouched and only the container changes. It takes a moment, and the quality is exactly the original's. When the codecs don't fit, the video is re-encoded at a very high bitrate.
High, Balanced and Smaller file always re-encode. High keeps detail for editing or archiving; Balanced is a good default for sharing; Smaller file lowers the bitrate and scales anything above 720p down to 720p, which is often enough for a phone screen or an email attachment and can cut the size by more than half.
What to expect
Re-encoding speed depends on your device and the resolution of the video. On a recent laptop, 1080p usually converts faster than it plays. Very large files, above about 500 MB, can run out of browser memory, so the tool warns you first; trimming the video into shorter parts helps. Browsers without the WebCodecs video encoder fall back to FFmpeg running in the page, which downloads once from WeaveAI's engine server and is slower but works the same way.
Questions
- Is my video uploaded?
- No. The video is converted inside your browser, by its own video encoder or by FFmpeg running in the page. Your video never leaves your device.
- How long does converting take?
- Keeping the original quality from MOV to MP4 is near instant, because the video is only repackaged. Re-encoding runs at about real time to several times faster, depending on your device and the video's resolution; a one-minute 1080p clip usually takes under a minute.
- Which format should I pick?
- MP4 with H.264 plays almost everywhere: phones, Windows, Macs, social networks and messaging apps. WebM is smaller for the same quality and suits websites, but some Apple apps don't play it.
- Is there a size limit?
- No fixed limit, but the result is held in your browser's memory, so files above about 500 MB can fail on phones or with many tabs open. The tool warns you before you start.