How this video merger works
A video merger joins several clips into one file that plays them one after another. You choose two or more videos, set the order, and VimCut writes a single MP4 that contains all of them in sequence. Your original files are not changed.
Each clip is scaled and padded to one shared size and frame rate, so a portrait clip and a landscape clip can play in the same file. A clip with no sound gets a silent track, which keeps the joined file working in other players and on upload sites. The work runs on WebAssembly (ffmpeg.wasm), and every clip is loaded into memory, so many large clips take longer. The merged file is saved as a single MP4. Drag a clip to reorder it, or use the up and down buttons, and add or remove clips before you click Merge Videos.