Merge Videos
Pick the files in the order you want and download the single video. It runs in your browser with ffmpeg in WebAssembly: nothing is uploaded, which also means there is no server-imposed size limit — only your tab memory.
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How it works
The fast path uses the concat demuxer with -c copy, which requires the same codec, resolution and frame rate across all files — it merely splices packets. When that fails, the tool falls back to the concat filter, which decodes and re-encodes everything with libx264. That is the difference between seconds and minutes, so recording clips in the same format pays off.
- Stream-copy join when the files are compatible, nearly instant
- Detects incompatibility and re-encodes automatically, warning you it will be slow
- No limit on file count beyond available memory
- Preview and direct download, no watermark