Join audio files
Several recordings, one file, in your order.
Drop files here
or click to choose from your deviceAccepted: MP3, M4A, AAC, WAV, OGG, OGA, OPUS, FLAC, WEBA
Up to 20 files per runUp to 150 MB per file5 runs per dayRemove limits with Pro✓ Works offline
Your files stay on your device
This tool runs entirely in your browser. Nothing is uploaded, nothing is stored, and you can even turn off your internet connection before you start.
Example
Example: a Spanish listening quiz from six recordings, two seconds between them
A high-school Spanish teacher builds a listening quiz: an intro recorded on her phone (00-intro.m4a, 48 kHz) and five dialogues from a USB microphone (01-dialogo.wav to 05-dialogo.wav, 44.1 kHz). She adds them in that order, then picks Save as “MP3”, Bit rate “128 kbps”, Pause “2 s”.
- Mixed formats and rates do not matter: every file is decoded and brought to the highest rate among them, 48 kHz, then laid end to end.
- The pause goes only between files, never at the start or the end: 6 files, 5 pauses of 2 seconds.
- Length: 0:25 + 1:10 + 0:55 + 1:32 + 1:05 + 1:48 = 6:55, plus 10 seconds of pauses = 7:05.
- The file is named after the first one with -joined: 00-intro-joined.mp3.
| File | Length | Starts at |
|---|---|---|
| 00-intro.m4a | 0:25 | 0:00 |
| 01-dialogo.wav | 1:10 | 0:27 |
| 02-dialogo.wav | 0:55 | 1:39 |
| 03-dialogo.wav | 1:32 | 2:36 |
| 04-dialogo.wav | 1:05 | 4:10 |
| 05-dialogo.wav | 1:48 | 5:17 |
One MP3 of 7:05, about 6.8 MB at 128 kbps (10.2 MB at the preset 192 kbps), small enough to attach to an email or post for the class. If the phone intro is louder than the dialogues, run the result through the volume tool with normalise on.
How it works
- Add the files in the order you want them. Drag them up and down if the order is wrong.
- Choose a gap if the pieces should not run straight into each other — half a second is enough to stop two sentences colliding.
- Pick the format. MP3 is the safe answer; WAV if this is going into an editor afterwards.
- Press join and the single file downloads.
Frequently asked questions
- Do the files have to be the same format?
- No. They are all decoded first, so an MP3, a WAV and an M4A join together perfectly well and come out as whichever format you choose.
- Does the pause go at the start or the end too?
- No, only between files. Six files with a 2-second pause get five pauses, 10 seconds in all: the first file starts at 0:00 and the recording ends with the last one.
- What is the joined file called?
- The first file’s name with -joined and the ending of the format you chose: 00-intro.m4a first and MP3 chosen gives 00-intro-joined.mp3. Numbering your files 01, 02 and so on also keeps them in order when you add them.
- Will the volume jump between pieces?
- It can, if the recordings were made at different levels — nothing here changes the loudness. Run the result through our volume tool with normalise on and the jumps flatten out.
- Is there a limit on how many?
- On the free plan, up to 20 files a run, each up to 150 MB, 5 times a day; Pro removes these limits. An hour of MP3 is about 60 MB, so there is room. Beyond that, your device’s memory is what counts, since all the work happens there.
- Is anything uploaded?
- No. The joining happens in your browser.