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
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.
Is the merge lossless?
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It is whenever the inputs already agree — the encoded data is copied straight through. It stops being lossless only when the inputs disagree and something has to be re-encoded to make them compatible, and even then it is one pass, not one per file.
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.
Does Merge Video cost anything?
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No. Merge Video is free without an account, and the output has no watermark, corner logo or intro card. The upload and the result are deleted automatically about 24 hours after the job, which leaves time to download the result.
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 does a MP3 site host Merge Video?
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MP3.to is built around the format that made portable audio ordinary: universally playable, small enough to ignore, and lossy in a way that only matters if you keep re-encoding it. Audio jobs cluster: the same person who needs a format changed usually needs the file cut, levelled or made smaller in the same sitting. Putting Merge Video behind the same upload, the same caps and the same account is what turns three tabs into one.
What should I do with the result once Merge Video is finished?
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The converter on this site moves audio between MP3, WAV, FLAC, M4A, OGG and Opus, so the output format is a decision you can leave until the end rather than commit to at the start. Doing that after Merge Video rather than before means the encode happens once, on the file you actually settled on, instead of twice.
Is Merge Video here the same tool the sibling sites run?
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The engines are shared — the same ffmpeg build, the same workers, the same limits. What a MP3 site adds is a point of view about bitrates, about what survives an encode and about when a lossless intermediate is worth the upload time. It also starts from one fact about the format this site is named after: MP3 frames are fixed-size blocks, so a cut lands on a frame boundary and gapless playback markers do not survive a re-encode.
Do I need an account, and does anything get kept?
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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.