Audio Joiner
Merge multiple audio files into a single track with custom ordering and smooth crossfades. Processing runs entirely in your browser without file uploads.
MP3, WAV, M4A, AAC, OGG, FLAC, Opus · joined in order · up to 1 GB
Tips
- The browser downloads a 30 MB engine once on first use, after which merging works offline.
- Drag and drop files in the queue to rearrange their playback order before merging.
- Set crossfade durations to one or two seconds so track beginnings are not cut off.
How to use it
- 1 Add or drag your audio files into the queue.
- 2 Reorder the tracks in the list to match your desired playback sequence.
- 3 Adjust transition settings such as silence intervals or crossfade length.
- 4 Process and export the merged audio file directly to your device.
What you should know
Podcasters, musicians, and voiceover artists often need to combine multiple recordings, background music, and intro segments into one cohesive track. Audio files frequently vary in sample rates like 44.1 kHz or 48 kHz, channel layouts from mono to stereo, and encoding bitrates. Merging disparate streams requires decoding each source into raw PCM audio, equalizing their sample rates and channel counts, and concatenating them sequentially. Direct stream copying fails when format parameters differ, so re-encoding to a standard output container like MP3, AAC, or WAV ensures uniform playback across all media players and mobile operating systems.
This tool concatenates your audio clips in the exact sequence you specify in the browser. You can arrange the list order and configure seamless crossfades or insert precise silence intervals between tracks to prevent abrupt transitions. Because processing happens locally using WebAssembly, your original source files never upload to an external server. The engine runs on a single thread inside the browser tab, meaning combining multiple lengthy or uncompressed audio files requires active tab processing time directly proportional to the total audio duration and selected output bitrate.
Frequently asked questions
Do all input files need to be in the same audio format?
No, you can combine different formats like MP3, WAV, AAC, and OGG; the tool decodes and standardizes all streams into your chosen output format.
Why does merging take longer for longer audio files?
The audio engine runs single-threaded directly inside your browser tab, meaning processing time scales with the total audio duration and re-encoding complexity.
Are my audio files sent to a remote server?
No, all file decoding, concatenation, and encoding execute entirely within your local browser memory, keeping your recordings private.
Guides
Articles and format references related to this tool.
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