Video Merger
Merge multiple videos into one
Merge multiple videos into one Runs locally in your browser
About the
The Video Merger joins two to ten clips into a single MP4, entirely in your browser. It uses ffmpeg's concat filter to align video and audio streams from every input, then re-encodes once so the result plays everywhere.
Because the merge re-encodes, it also normalises small differences between clips. For the cleanest result, feed it files from the same source: same camera, same resolution, same frame rate. Drag the list to reorder clips before merging.
Everything is local: nothing is uploaded, there is no queue, and no watermark is added to the output.
Where people use the
- Stitching several takes into one continuous video.
- Combining an intro and outro onto a main clip.
- Assembling a day's footage into a single shareable file.
How to use the
- 1
Add clips in order
Select multiple videos. They appear in a numbered list; use the arrows to reorder before merging.
- 2
Check compatibility
Best results come from clips with the same resolution and codec. Mixed sources may fail or show artefacts.
- 3
Merge
Click merge. All clips are read, then concatenated and encoded in one pass. Keep the tab in the foreground.
- 4
Download the MP4
The merged file is ready for download as soon as encoding finishes.
Tips and best practices
- Merge clips from the same device whenever possible.
- If a clip has no audio track, the merge can still work but check the output sound.
Frequently asked questions
Why did my merge fail?
The concat filter needs matching streams. Different resolutions, codecs or missing audio tracks are the usual causes. Convert clips to MP4/H.264 first with the Video Converter.
Is there a limit on how many clips?
Ten clips, which is the practical limit for browser memory and encoding time.
How long does it take?
Roughly the combined duration of all clips at encoding speed, plus a few seconds of setup. Ten short clips merge in well under a minute.
Does merging lose quality?
The output is re-encoded to H.264 at a high-quality preset, so there is minor generation loss. For same-source clips the result is effectively transparent.