Merge clips
Concatenate two or more clips into one file.
This runs in your browser. Nothing is uploaded. Longer clips take longer here than they would on a fast server — that is the trade-off for not sending the file.
About Merge clips
Joins two or more video clips into one file in your browser with FFmpeg concat, without uploading the parts to a merger site.
Concatenate is the least glamorous FFmpeg job and the one upload sites love to charge for after the third file. Drop two or more clips, in the order you want them. The page writes a concat list into the wasm filesystem and re-encodes to a common MP4 or WebM so mismatched codecs do not produce a file that only VLC understands.
Order is the order of the list, which is the order you added files. There is no drag-to-reorder. If you dropped them wrong, Try another and drop again. Audio and video both get re-encoded, so a pair of 4K clips will take a while and may exhaust memory.
Resolution differences get scaled by FFmpeg’s concat+encode path rather than a pretty letterbox UI. If you care about matching 1080p before the join, resize each clip first. I am not going to hide a surprise crop.
Titles, fades, and music beds are an editor. This page is “clip A then clip B, one file, still on my laptop.”
How to use Merge clips
- 1Drop the first clip, then add the rest in order.
- 2Check the file list.
- 3Click Merge, then Download.
What it won't do
- No reorder handle, no transition effects.
- Always re-encodes the join.
Common questions
Can I reorder clips after dropping them?
Not in the list UI. Reset and drop in the order you want. A drag handle would be nicer; it is not what shipped.
What if the clips have different sizes or frame rates?
They are re-encoded onto one timeline. You may see stretching or a frame-rate change. Matching them first with Resize is the predictable path.
Is there a limit on how many clips I can merge?
The limit is memory. Five short screen recordings are fine. Fifty camera originals are how you crash a tab. The 1.5 GB warning still applies to the total.
Related tools
Why this one doesn't upload your file
There is no server to upload to. This page is a static file, and the work happens in your browser using the same graphics and WebAssembly code that renders every other site you visit. Your file is read from disk into memory, processed, and handed back as a download. Once the page has loaded you can disconnect from the network entirely and it keeps working. The longer explanation