1Upload every file you want combined — at least two of them.
2Add the files in the order you want them joined; the first file you add comes first.
3Start the merge; the files are joined one after another into a single file.
4Download the single combined Video file.
Merge Video FAQ
Does it matter if the inputs are different formats?
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It does. this format is read and written by the same streaming pipeline as everything else we support. Matching inputs take a fast, lossless path; mismatched ones have to be reconciled to a common format, which is slower and costs one encode.
Anything specific to Video when merging?
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Yes — the container and codec are probed before anything runs, so mixed uploads in one batch are handled per file. That is worth checking when the inputs did not all come from the same source.
How does Merge Video join the files together?
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Concretely, matching clips are concatenated without re-encoding and mismatched ones are normalised to a common format first, so you get the fast path whenever the sources permit it. Upload everything you want combined and the result comes back as a single file.
Which video formats does Merge Video accept?
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MP4, MOV, MKV, WebM, AVI, WMV, FLV, 3GP, M4V, MPEG and MPG. Each file is probed for its real container and codec before anything runs, so a mixed batch is handled correctly file by file.
Is there a file size limit on Merge Video?
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Yes: free accounts process video up to 40 MB per file whichever container you brought; ffmpeg with x264, x265 and libvpx does the encoding. It is high enough that upload speed is usually the binding constraint rather than the cap itself.
Why would a modern-format site run Merge Video?
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WEBP.to is built around the modern replacement for both of the old defaults: one format that does lossy, lossless, alpha and animation, and reliably lands smaller than the JPEG or PNG it came from. People arrive here having decided the old defaults are costing them bandwidth, and that decision immediately raises the rest: what size, what quality, what happens to the transparency. Merge Video is on the same upload and the same account so those questions get answered in one place.
Once Merge Video has run, what is worth doing next?
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The converter on this site moves images to and from WebP, PNG, JPG and AVIF, which is where you decide whether a smaller file is worth losing the older browsers. Doing it in that order matters: pick the pixels first and the container afterwards, because the container is the cheap decision and the pixels are the expensive one.
Do the sibling sites run something different?
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The engines are identical — same libraries, same workers, same caps. What is different is the opinion attached, and the opinion here rests on a property of the format this site is named after: the same .webp extension can hold a lossy VP8 frame, a lossless one, or an animation, so the sensible processing path is decided per file rather than per extension.
What happens to my file, and is an account required?
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No account is needed. Uploads and results are kept for about 24 hours, which leaves time to download the result, and are then deleted automatically; nobody reads, lists or indexes them. Several files in one job need a paid plan.
