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 Opus file.
Merge Opus 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.
How does Merge Opus join the files together?
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Concretely, files that already share a codec, sample rate and channel layout are concatenated by copying the encoded frames, so the join costs nothing in quality; mismatched inputs are decoded and re-encoded once to a common format. Upload everything you want combined and the result comes back as a single file.
Can I run Merge Opus on several Opus audio files at once?
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Yes. Upload the set and they process in parallel with the same settings, which is the practical way to handle a podcast series or an album rather than repeating the job by hand.
Does Merge Opus cost anything?
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No. Merge Opus is free without an account, and nothing is added to the audio. 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 Opus?
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MP3, AAC, M4A, OGG, Opus and WMA are the lossy codecs handled directly, and lossless sources (WAV, FLAC, AIFF) can go in the same batch. The codec is probed from the stream, so an incorrectly named file still works.
Does Merge Opus belong on a site about a photo format?
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JPEG.to is built around the format that carries nearly every photograph in existence — thirty years old, opened by literally everything, and still the right default for a photographic image. The jobs people bring here are the ones a photograph collects over its life — too big to email, wrong dimensions for a form, wrong way up out of a phone. Merge Opus runs on the same upload and the same account as the conversions because that is where those jobs land.
What is the sensible next step after Merge Opus?
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The converter on this site moves images to and from JPEG, PNG, WebP and HEIC, which is where the trade between file size and one more generation of loss gets settled. Deciding the format last rather than first is the whole point: every extra save of a photographic image is another generation, and the fewer of them you spend, the more of the picture survives.
Is this the same engine as the other converter sites?
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Yes — the same libraries, the same workers, the same caps. The difference is which advice is on the page, and here that advice is built on one property of the format the site is named after: the .jpeg and .jpg extensions are the same bitstream, so nothing here behaves differently from a .jpg — only the filename changes.
Is anything kept, and do I need to sign in?
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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.
