No upload, 100% local, no account

Merge audio files

Drop your audio files, drag to reorder them, and download the merged result. Everything runs in your browser, nothing is uploaded.

How Merge audio files works

Audio merge concatenates multiple audio files into a single track, drag to reorder them, then download the combined result as one file. It is the right tool for stitching podcast segments, joining voice memos, assembling a playlist into one recording or combining music parts recorded separately, with FFmpeg compiled to WebAssembly.

Drag the files into the order you want and the output follows it exactly. FFmpeg normalizes format and sample rate during concatenation, so you can merge an MP3 with a WAV, and an optional crossfade smooths the joins.

Frequently asked questions

Are my files uploaded to a server?

No. ffmpeg compiled to WebAssembly joins your tracks in this browser tab, each file is read into memory on your own device and combined there (back-to-back, or with the acrossfade filter for smooth crossfades and afade for fade-in/out), and the merged audio is offered as a local download. Nothing reaches Sunasty or any third party. Open your browser's DevTools, go to the Network tab and watch: no request carries your audio.

Can I reorder the tracks before merging?

Yes. Drag and drop the files in the list to set the order you want. The merged output will follow that sequence exactly.

Do all files need to be the same format or sample rate?

Not necessarily. FFmpeg normalizes the format and sample rate during concatenation, so you can merge an MP3 with a WAV as long as the output format supports them. For best results and fastest processing, files with the same codec and sample rate merge cleanest.

Does it work offline?

Yes, once the page has loaded. Because the processing happens on your device, you can disconnect from the network and the tool keeps working. This is the clearest proof that your data never leaves your machine.

Is it free? Do I need an account?

It is completely free and requires no sign-up. There are no watermarks, no daily limits and no tracking cookies needed to use the tool.