1Upload every file you want combined — at least two of them.
2Drag the uploaded items into the order you want; the order is taken from the list, not from the filenames.
3Start the merge, which joins matching inputs without re-encoding them and reconciles mismatched ones exactly once.
4Download the single combined Video file.
Merge Video FAQ
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.
Can I control the order things are joined in?
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Yes — drag the uploaded items into the order you want before starting. Order is taken from the list, not from the filenames, so "IMG_2.jpg" sorting after "IMG_10.jpg" is not a problem you have to solve first.
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.
Will Merge Video lower the quality of my videos?
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Only if the operation requires re-drawing frames. Container-level and timeline-level work is done as a stream copy, which is bit-identical to the source and finishes in seconds. Anything that must re-encode does so at a quality level you choose.
Can I run Merge Video on several videos at once?
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Yes, and it matters here more than anywhere else — video jobs run in minutes, so queueing the batch in parallel is the difference between one wait and several.
What happens to audio, subtitle and chapter tracks?
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They are carried across wherever the target container can hold them, including multiple audio languages, embedded subtitles and chapter markers, rather than silently keeping only the first track of each.
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. Uploaded video is deleted from the workers shortly after the job completes.
Why does a WebM site host Merge Video?
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WEBM.to is built around the container the open web actually chose — VP9 or AV1 with Opus audio, decoded natively by every modern browser and needing no plugin, licence or player. Video is the case where extra round trips hurt most — the files are large and every upload costs real minutes. Running Merge Video on the same pipeline as the conversions means one upload covers the whole job instead of one upload per tool.
What should I do with the result once Merge Video is finished?
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The converter on this site moves video between WebM, MP4, MKV, MOV and the rest, or pulls the soundtrack out entirely, without another upload. Sequencing it that way matters more for video than anywhere else: each re-encode is another generation, so the fewer of them stand between the source and the file you publish, the better it looks.
Is Merge Video here the same tool the sibling sites run?
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The engines are shared — the same ffmpeg build with x264, x265 and libvpx, the same workers, the same limits. What a WebM site adds is a view on containers and codecs: which combinations play everywhere, which need a re-encode and which can simply be copied across. It also starts from one fact about the format this site is named after: WebM is VP9 or AV1 with Opus audio, which browsers decode natively but which most desktop editors still transcode on import.
Do I need an account, and does anything get kept?
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No account, and nothing is kept: uploaded video is deleted from the workers shortly after the job finishes, nothing is watched and nothing is indexed. Free accounts exist for history and batch size, not for access.