Combine 2 to 10 video clips into one file, processed entirely in your browser, files never uploaded.
Your videos are merged locally with FFmpeg running in your browser. Nothing is uploaded; the files never leave your device. First use downloads the ~31 MB engine once. 2-10 files, each up to 200 MB.
Files merge in listed order; remove a file and re-select it to change its position.
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Joining clips is one of the most common editing chores: stitching camera takes into one scene, assembling tutorial parts recorded at different times, or combining screen recordings into a single walkthrough. This tool merges 2 to 10 video files into one output, in exactly the order you list them, without any uploading, which matters for unpublished or client footage.
When all clips share the same codecs and container, merging uses stream copy: the compressed data is concatenated as-is, so quality is untouched and even sizeable files join in seconds. When the formats differ (for example an MP4 followed by a WebM), stream copy cannot work, so the tool automatically falls back to re-encoding everything to a compatible H.264 MP4: slower, especially for big files, but it always produces a valid result, and the result text tells you which path ran. Everything executes in your browser via WebAssembly.
For best results, prepare your clips first: cut them to length with the Video Trimmer, normalize them to one format with the Video Converter (which also makes the fast no-re-encode path more likely), and shrink the merged output with the Video Compressor if it ended up larger than you need.
Mismatched codecs or containers cannot be stream-copied into one file, so the tool automatically falls back to re-encoding every clip to H.264 video with AAC audio in an MP4 container. This takes longer (big files re-encode slowly in a browser), but the result always plays. The result message tells you which path ran.
Not when it can be avoided. If all clips share the same codecs and container, the compressed streams are concatenated as-is: quality is identical and merging takes seconds. Re-encoding happens only in the automatic fallback for mismatched inputs.
Between 2 and 10 files, each up to 200 MB. Note that browser-based processing is bound by your device memory; merging many large files at once, especially through the re-encode path, may fail on machines with little RAM.
Yes. Files merge in the exact order they are listed. Click Remove on a file, then re-select it; newly picked files are appended to the end of the list, so repeat as needed until the order is right.
No. Merging happens entirely in your browser using a WebAssembly build of FFmpeg. Files are read into browser memory, joined locally, and returned as a single download; nothing is transmitted anywhere.