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 M4V file.
Merge M4V FAQ
Anything specific to M4V when merging?
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Yes — M4V is structurally an MP4, but a FairPlay-protected one cannot be processed at all — only unprotected files go through. 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 M4V join the files together?
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Concretely, clips with matching codec, resolution and frame rate are concatenated as a stream copy and the join is instant; anything mismatched is normalised to a common format first, which is the slow path but the only correct one. Upload everything you want combined and the result comes back as a single file.
Does Merge M4V cost anything?
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No. Merge M4V 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.
What can I upload to Merge M4V?
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MP4, MOV, MKV, WebM, AVI, WMV, FLV, 3GP, M4V, MPEG and MPG. The container and codec are probed before anything runs, so a mixed batch is handled correctly per file rather than assumed to be uniform.
Is there a file size limit on Merge M4V?
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Yes: free accounts process video up to 40 MB per file, by far the most generous cap on the site; ffmpeg with x264, x265 and libvpx does the work, which is the same toolchain behind most desktop video software. Video is the one family where the cap is high enough that upload time, not the limit, is what you will actually notice.
Why does a MP3 site host Merge M4V?
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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 M4V 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 M4V 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 M4V rather than before means the encode happens once, on the file you actually settled on, instead of twice.
Is Merge M4V 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.
