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 FLAC file.
Merge FLAC FAQ
Is the merge lossless?
+
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?
+
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?
+
It does. FLAC is lossless compression — bit-identical to the source on decode, at about half the size of WAV. 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 FLAC when merging?
+
Yes — FLAC decodes bit-identically to the source, so any number of edit-and-resave cycles cost you nothing in fidelity. That is worth checking when the inputs did not all come from the same source.
Will Merge FLAC lower the quality of my FLAC audio files?
+
No. Lossless audio is edited sample-exactly, so what comes back decodes bit-identically to what you would get doing the same edit in a desktop editor. You can repeat the cycle as many times as you like without accumulating any loss at all.
Can I run Merge FLAC on several FLAC audio files at once?
+
Yes, though lossless files are large, so the batch is bound by upload bandwidth rather than by processing. Settings apply uniformly across the set.
Are bit depth and sample rate preserved?
+
Yes, unless you change them deliberately. A 24-bit/96 kHz source stays 24-bit/96 kHz — nothing is silently downsampled to 16/44.1, which is the failure mode that makes a master unusable.
Does Merge FLAC cost anything?
+
No. Merge FLAC is free with no account required, and nothing is added to the audio. Uploads are deleted from the workers shortly after the job finishes.
Why does a WebM site host Merge FLAC?
+
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 FLAC 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 FLAC is finished?
+
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 FLAC here the same tool the sibling sites run?
+
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?
+
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.
