Free tool
Free video merger that joins clips in your browser
Join two to five video clips into one file.
Your clips
Drag a file here, paste it, or choose one.
.mp4, .mov, .webm, .mkv. Up to 500 MB.
Add up to 5 clips. Pick several at once or one at a time.
Your clips never leave your browser. The join runs on this machine.
Result
Worked example
Measured on our own launch film added twice, 27 seconds each, both matched to 1920 by 1080.
Two clips in
15.2 MB
Joined, 0:54
7.4 MB
The joined video runs to 54.4 seconds, which is both clips end to end. Most of the time went on matching the clips. The join itself copies the streams, so it is quick.
1. Add your clips. 2. Put them in order. 3. We match them up. 4. Join and download.
What Interlace does
One video, one style, one voice.
- Start from a script, a document or a prompt
- Every scene drawn in the same visual style
- One narrator from start to end
Real Interlace output, unedited. Shown silent and sped up.
Your clips
intro.mp4
part-2.mov
outro.mp4
Questions
Asked and answered
No. The file is read by the page, handed to ffmpeg compiled to WebAssembly, and written back out, all on your own machine. There is no upload step, and closing the tab discards everything.
The first clip sets the output size. Every other clip is scaled to fit inside that frame and padded with black where the shape does not match, so nothing is cut off. Merging clips of the same size avoids the bars entirely.
All the clips have to sit in the browser tab's memory at once, alongside the output. Five is what we can promise inside the 500 MB total budget. Merge in batches if you have more.
A silent track is generated for any clip that has no audio, so the sound on the other clips does not slide out of sync.
500 MB and 10 minutes. Everything runs inside one browser tab, and a tab has a fixed memory budget. Past those limits the run gets slow or fails outright, so a desktop encoder is the better tool.
The WebAssembly build here is single threaded, on purpose. The multi threaded build needs cross-origin isolation headers that would break embedded video elsewhere on this site. Expect roughly real time on a modern laptop, so a two minute clip takes about two minutes.
Turn this into a video
Create an account and start from a document, script, or prompt.