Engineering
Bleep and redact audio without uploading it anywhere
An AI model runs in your browser, transcribes your audio, and bleeps the words you pick. No server, no upload, no account. Your recording stays on your device.
6 min readRead more →
utility
Join Audio Files Online
Merge multiple audio files into one with optional crossfade. Free, private, runs in your browser.
How it works
01
Drop multiple audio files or click to upload. MP3, WAV, and most formats work.
02
Reorder tracks with the arrow buttons. Set crossfade duration if you want smooth transitions.
03
Click merge, preview the result, and download as WAV.
No file uploadNo signupNo ads100% browser-based
Frequently asked questions
How do I merge audio files online?
Upload two or more audio files to this tool. Arrange them in your desired order using the arrow buttons. Optionally set a crossfade duration for smooth transitions. Click merge and download the combined file.
How many files can I join at once?
No limit. Add as many files as your device's memory can handle. Each file is decoded in your browser and merged locally.
What is crossfade?
Crossfade overlaps the end of one track with the beginning of the next, fading one out while fading the other in. This creates a smooth transition instead of an abrupt cut. Set the duration from 0 to 5 seconds.
Can I merge files with different formats?
Yes. You can mix MP3, WAV, OGG, FLAC, M4A, and other formats. The browser decodes each file, and the merged output is a single WAV file.
Does this upload my files to a server?
No. All processing happens locally in your browser. Your files never leave your device.
Can I reorder the tracks after uploading?
Yes. Use the up and down arrow buttons next to each track to change the order. The merge follows the displayed order.
Is this audio joiner free?
Completely free. No account, no limits, no watermarks.
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