Video, Audio & YouTube
Merge videos into one MP4, even with different formats
Add clips from different cameras or phones. Each one is fitted to one canvas without stretching, and you get a single MP4 plus a table of what changed.
or drop them here
- clip-1.movLandscape 16:9
- clip-2.mp4Vertical 9:16
- clip-3.webmClassic 4:3
Fitted to the canvas of the first clip
- 1 · fills the frame
- 2 · bars left and right
- 3 · narrow side bars
joined.mp430 fps · H.264 · AAC audio at 48 kHz
- compatibility-matrix.json
- segment-map.csv
Canvas options: first clip, 1080p landscape or 1080p vertical. Transition: hard cut or crossfade.
One clear job, from source to download
- 1
Add the source
Supported formats and limits are visible before the upload.
- 2
Confirm the settings
Review the exact source, options, units and access before processing.
- 3
Inspect and download
Check the preview and warnings, then unlock the complete package.
Joining clips from different sources into one MP4
What you bring
You bring the clips you want to join as MP4, MOV, WebM or MKV, up to 5 minutes. They can come from different cameras or phones. Each file is read first, and a table shows where resolution, frame rate, codec or audio layout differ. You see this before anything is encoded, so you know which clips need converting and which already match.
What you get back
You get the joined MP4, a compatibility table and a segment map. The table shows how each clip differed and what was converted. The segment map records which source sits in which part of the timeline. When all clips already share the same codec and settings, they are joined without re-encoding, so no quality is lost. Play the joins in the result and check them against the segment map.
Canvas, transitions and conversions you approve
You choose the output canvas: the size of the first clip, 1080p landscape or 1080p vertical. Between clips you get a hard cut or a crossfade. A crossfade has to be rendered, so the clips can no longer be joined without re-encoding. Clips are never stretched, changed in frame rate or given a new audio layout without telling you. Mixing HDR and SDR footage is blocked unless you choose a conversion.
Questions before you run it
Can I join clips recorded on different cameras?
Yes. Each file is read with ffprobe first, and the compatibility matrix shows where resolution, frame rate, codec or audio layout differ before anything is encoded.
What does stream-copy mean here?
When every clip already shares the same codec and parameters, the streams are concatenated without re-encoding, so no generation loss is added. Anything else needs a conform step you approve.
What happens if I mix an HDR clip with SDR footage?
That combination is blocked unless you choose a conversion. It is never merged silently, because an unmanaged mix leaves washed-out or crushed sections.
Which canvas does the joined file end up in?
The first clip, 1080p landscape or 1080p vertical, whichever you pick. The segment map records which source occupies which part of the timeline.
Can I put a transition between clips?
A hard cut or a crossfade. A crossfade has to be rendered, so stream-copy is not available once you choose it.