AUDIO + AUDIO -> ONE · Local tool
Audio Joiner
Join several audio files end to end, in the order you choose.
Last updated
How do I join several MP3 files into one?
Drop the files onto filetity's audio joiner, put them in the order you want with the arrows on each row, and join. They are written end to end with no gap and no crossfade, in exactly the order shown, which matters because a file picker rarely hands over chapters or takes in the order a person wants them. Formats can be mixed freely: MP3, WAV, M4A, OGG, FLAC and AAC all decode on the way in. Files that disagree on sample rate or channel count are brought up to the highest present rather than down to the lowest, because raising costs a few bytes and loses nothing while lowering would throw away material from the better files, and the page names which files it is going to change before it runs. Everything happens in the browser tab with nothing uploaded.
01 / Your device
the file stays here
02 / Browser memory
the work runs locally
03 / Back to you
saved on this device
When you would use this
Situations, not settings.
- Chapters or takes recorded separately
- Put them in the order you want with the arrows and get one continuous file, rather than the order the file picker happened to hand over.
- Voice notes that should be one message
- Six clips from a chat app become one file somebody can play through without tapping. Mixed formats are fine, since each is decoded on the way in.
- An audiobook or a lecture series in pieces
- Joined end to end with no gap, and files that disagree on sample rate are brought up to the highest present rather than down to the worst.
How it works / no cloud
A conversion engine, not an upload form.
Each file is decoded to samples in turn and written into one output with a running timestamp, so only one file is held in memory at a time whatever the number. Files that disagree on sample rate or channel count are brought up to the highest of what you gave, because raising costs bytes and loses nothing while lowering throws material away.
- Offline ready
- Installable app
- No file limit queue
Straight answers
No accordion. Nothing hidden.
- Is it free?
- Yes, with no watermark and no page limit.
- Does it need an account?
- No. There is no account system.
- Is my file processed on my device?
- Yes. The file is read by your browser and never uploaded. There is no server to send it to.
- What formats are supported?
- MP3, M4A, WAV, OGG, FLAC and AAC in, mixed freely. MP3, M4A, OGG or WAV out.
- What are the limits?
- Files are joined end to end with no gap and no crossfade. There is no cap on how many, but the finished file is held in memory before you save it.
- Does it work on mobile?
- Yes, on any modern mobile browser. Large files are limited by the memory the phone gives the browser.
- Does it work offline?
- Yes, once the page has loaded. The tool keeps working with no network connection.
- What if my files have different sample rates?
- They are all brought up to the highest one present, and the page names which files are being changed before it runs. Raising a rate costs a few bytes and loses nothing; lowering it would throw away material from the better files to match the worst one, which is the wrong way round.
- Can I control the order?
- That is the point of the list. Files arrive in whatever order the picker handed them over, which is rarely the order you want for chapters or takes, so each row has arrows to move it and the join follows the list exactly as shown.
- Is there a gap or a crossfade between files?
- Neither. Each file starts exactly where the previous one ended. If you want a pause between tracks it has to be in the files themselves, and if you want a crossfade this is the wrong tool: that needs an editor that can overlap and fade two regions.
- Can I mix formats in one join?
- Yes. Drop MP3s, WAVs and M4A files together and pick one output format; each is decoded on the way in, so what they arrived as makes no difference to the result. This is the usual case when the pieces came from different devices.
- Do the track names or tags survive?
- No, and they cannot: the output is one continuous track, so there is nowhere for six separate titles to go. What you get is a single file with a single name, which is the point of joining, and you can tag it afterwards in a music library if that matters.
Keep working locally
3 available · more coming