No upload · No software · Runs in your browser
Audio Joiner — Merge Audio Files
Combine multiple audio files into one in your browser. Drop in up to 10 files in any format — MP3, WAV, M4A, FLAC, OGG, AAC, Opus, AIFF — reorder them as needed, and join them into a single MP3. The whole pipeline runs locally with FFmpeg WebAssembly. Your audio never leaves your device.
Drop audio files here or click to browse
Any audio format · Max 20 MB each · Up to 10 more
How it works
- 1Add up to 10 audio files by clicking 'Add files' or dragging them into the dropzone.
- 2Reorder the files using the up and down arrows — the joined output follows your order exactly.
- 3Remove any file you don't want by clicking the × button next to it.
- 4Click 'Join Files' to concatenate all tracks into one MP3 at 192 kbps.
- 5Download the result when the progress bar completes.
Use cases
Combine podcast segments
Record different segments of your podcast episode separately — intro, interview, outro — then join them into the final episode file. Eliminates the need to record everything in one session and keeps retakes manageable.
Create a continuous music mix
String together individual tracks into a continuous playlist file for background music at events, DJ mix archives, or workout playlists where you don't want gaps between songs.
Merge split audiobook files
Some audiobooks are distributed as multiple chapter files. Join them into a single file so you can load one track into any player without worrying about chapter continuity or file order.
Concatenate voice memo recordings
Recorded a long interview or meeting across multiple voice memo files? Merge them into one continuous recording for easier transcription, sharing, or archiving.
Join music production stems
Producers assembling a track from separate stems — drums, bass, lead — can use the joiner to sequence them into a reference arrangement before moving to a DAW.
Assemble audio from multiple takes
Narrators and voice-over artists who record section by section can join the approved takes into a finished file without touching a desktop editor for simple concatenation jobs.
What this tool does — and what it doesn't
This tool performs simple concatenation: it plays File 1 from start to finish, then immediately plays File 2, and so on. The output is one file where all the inputs play back-to-back. It does not mix or layer audio — if you need multiple audio tracks playing simultaneously, you want a DAW like Audacity, GarageBand, or Reaper.
The tool also does not add crossfades, silence gaps, fade-ins, or fade-outs between the joined segments. What you put in is what you get out, in the order you specified. If you want a half-second gap between segments, add a short silent audio file between them. If you want a crossfade, a desktop editor is the right tool.
Why the output is always MP3
Joining audio from multiple different source formats (say, WAV + OGG + M4A) requires re-encoding to a single codec anyway — you can't concatenate different codecs without decoding and re-encoding. Rather than add a format-picker UI that creates confusion, we output MP3 at 192 kbps, which is audibly transparent for most material on typical playback gear and plays everywhere without compatibility issues.
If you need the joined output as WAV, FLAC, or another format, download the joined MP3 and run it through the format conversion tools (MP3 to WAV, MP3 to FLAC, etc). Two-step, but clean.
Privacy: nothing leaves your device
Every other online audio joiner works by uploading all your files to a server, stitching them there, and streaming back the result. We don't. FFmpeg runs in your browser as WebAssembly. All your files load into local browser memory, are processed entirely on your device, and the joined file is written to a local Blob you download. No upload step. No server logs. No temporary copies on a third-party server. Disconnect from the internet after the page loads and the joiner still works.
Other joiner pages
Frequently Asked Questions
What audio formats can I join?
MP3, WAV, M4A, AAC, FLAC, OGG, Opus, AIFF, and WMA are all supported as inputs. The output is always MP3 at 192 kbps, which ensures compatibility regardless of what mix of input formats you used. If you need a different output format, convert the joined MP3 using the format conversion tools.
How many files can I join at once?
Up to 10 files per join operation. For more than 10 files, join the first 10, then join the result with the next batch. For large batch concatenation workflows (dozens of files), FFmpeg on the command line with a concat demuxer is more efficient.
Is there a file size limit?
Each individual file is limited to 20 MB on the free tier (500 MB on Pro). The total size across all files is effectively limited by available browser memory — modern browsers handle several hundred MB without issues. For very large files or many files, a desktop tool is a better fit.
Will the join reduce audio quality?
Inputs get re-encoded to MP3 192 kbps during joining. For lossy inputs (MP3, AAC, OGG, M4A), this is one transcoding pass — essentially inaudible quality loss at 192 kbps on typical playback gear. For lossless inputs (WAV, FLAC, AIFF), you're encoding lossless to lossy MP3, which does reduce quality, but 192 kbps is audibly transparent for most material on typical gear.
Can I add silence or gaps between the joined files?
Not directly — the tool concatenates files with no gap. To add a gap, create a short silent audio file (use any audio editor or a text-to-speech service with silence, then export) and insert it between the files in the list. A 0.5-second silent MP3 at 192 kbps is about 12 KB.
Will the joined file play on all devices?
Yes. The output is standard MP3 at 192 kbps, which plays on every modern device — iPhone, Android, Windows, macOS, Linux, smart TVs, car stereos, and any audio app. MP3 has the broadest compatibility of any audio format.
Does the joiner work offline?
Yes, after the first page load. The FFmpeg WebAssembly bundle is cached by the browser on the first visit. After that, you can disconnect from the internet, add files, and join them with no network access. This also proves there's no server in the loop — your files never cross the network.
Read more
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What Is MP3? The Format Explained
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Lossless vs Lossy Audio: The Complete Guide
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