Merge audio files

How to merge audio files into one

1. 1

   Add two or more audio files

   MP3, WAV, M4A, FLAC, OGG and more, mixed freely: up to 50 files and 200 MB each.

2. 2

   Set the order and the joins

   Move files with the up and down arrows: the list order is the order you hear. Add silence or a crossfade between them.

3. 3

   Download the WAV or make an MP3

   The joined file builds as you go. Press Download WAV, or Audio to MP3 under the result to convert it without downloading.

What you get when you merge audio files here

Add two or more recordings and they play back to back in one file, in the order of the list. That suits chapters of an audiobook, takes of a song or a run of voice notes. There is no Merge button. The joined file is built as soon as two files are in the list, and rebuilt whenever you move a file or change a setting. A waveform and a player show it before you download. On October 20, 2026, three MP3s of 3, 2 and 1 minutes became one 6-minute file in about a second, in Chrome on a Mac. The file is named after the first one in the list, with -merged added.

The result is a WAV; here is how to get an MP3

The joined file is always an uncompressed WAV, 16-bit at 44.1 kHz. That makes it large, about 10 MB for each minute of stereo sound: in the same test, 9.6 MB of MP3s became a 61 MB WAV. For an MP3, press Audio to MP3 under the result. The WAV opens there without being downloaded. At the default 192 kbps, the 6-minute file became an 8.2 MB MP3 in about 4 seconds. That step encodes a new MP3 rather than gluing the original MP3 data together. So pick a bitrate at least as high as your best file: 320 kbps if one of them was 320.

Merging is not mixing

This tool puts files one after another. It does not lay one recording over another, so it cannot put a voice over background music or make two tracks play at the same time. The only place two files sound together is a crossfade. It overlaps the end of one file and the start of the next, for up to 5 seconds at each join, and the rest of every file plays alone. To lay music under the sound of a video, Add Audio to Video has a Mix with the original mode. For two audio files, there is no mixing tool on this site.

Silence, crossfade and the click at each join

Silence between files adds up to 10 seconds of quiet at each join and makes the result longer, which suits chapters and separate tracks. A crossfade overlaps neighbors so one fades out as the next fades in, which suits songs. It makes the result shorter by its length at each join: with 2 seconds, the three test files came to 5:56 instead of 6:00. Use one or the other: the silence field is hidden while a crossfade is set. Without a crossfade, every join still gets a 10-millisecond fade, too short to hear as a fade, because two files cut mid-wave meet with an audible click.

Different formats, sample rates and channels

Files do not have to match. Most formats are decoded by the browser itself. When it cannot read one, as Chrome cannot read AIFF or WMA, the page loads its 32 MB audio engine and decodes the file on your device. In one test, an AIFF, a WMA, an M4A, an Opus and a FLAC file joined in order. Every file is converted to 44.1 kHz as it is read, so a recording made at 48 kHz comes out at 44.1 kHz. A mono file among stereo ones plays on both channels, and the result is stereo if any file is stereo.

Frequently asked questions