Merge Videos
Join multiple clips into one file. Drag to reorder.
Choose video filess
or drop them anywhere on this page
MP4 · MOV · WEBM · MKV · AVI · WMV · FLV · M4V · 3GP · MPEG · +3
Processed on your device — never uploaded
How to merge videos
- Add all the clips you want to join.
- Drag the thumbnails to set the order.
- Choose a format and whether to re-encode, then merge and download.
About this tool
Joining video clips has two very different cost levels depending on whether the clips are compatible. When they share the same codec, resolution and frame rate, ffmpeg can concatenate them by copying the bitstreams directly — no decode, no re-encode, fast and lossless. When they differ, every frame has to be decoded and the output re-encoded to a consistent spec, which is where the time goes.
The re-encode toggle makes this explicit. Off by default, because compatible clips from the same camera or export pipeline are the common case. Turn it on when you are mixing footage from different sources — a phone clip, a screen recording, and a downloaded clip rarely share the same parameters.
Questions
Do all clips need the same resolution and frame rate?
For stream concatenation (re-encode off) the clips should have the same codec, resolution and frame rate. If they differ, enable re-encode — the tool will normalise everything to a common spec. Mixing a 4K clip with a 1080p one without re-encoding will produce a broken output.
How many files can I join?
There is no imposed limit. Adding many large files will consume memory proportional to the buffered data, so on a machine with limited RAM it is worth merging in batches. Ten to twenty clips of a few hundred megabytes each is comfortable on most modern laptops.
What transitions are available?
Cut (instant switch), fade to black, and cross-dissolve. Transitions require re-encoding the junction frames, so enabling a transition also enables the re-encode path regardless of the re-encode toggle setting.