Audio joiner: merge audio files into one
Merge MP3s, songs, and recordings into one file, in the order you choose.
10M+ files processed since 2021
More options
Free for the first hour, 10 times a day. No sign-up.
Play them at once instead? Mix audio
Hear the parts become one
Play each part, then the joined file.
Voices in these examples are AI-generated.
How to merge audio files
- 1
Add 2 to 20 files.
- 2
Put them in order, top to bottom.
- 3
Download one merged file.
One after another
Audo's audio joiner merges 2 to 20 files, audio (WAV, MP3, M4A, AAC, FLAC, OGG, Opus, WebM, AIFF) or video (MP4, MOV, MKV, WebM, AVI), each up to 100 MB without an account, and the first hour of the merged file is free, 10 times a day, with no sign-up. Files about 3 minutes long in all usually merge in about 7 seconds.
Merging plays your files one after another, as one file: an intro, an episode, and an outro; the chapters of an audiobook; or a recording that was saved in parts.
Files recorded at different times are often at different levels, so Make the files equally loud matches them first and nothing jumps out. A crossfade fades one file out while the next fades in, which makes the merged file a little shorter than the parts added together. To trim a file before merging, use Cut audio.
Questions
Is there a free way to merge songs online?
Yes. Audo's audio joiner merges songs, MP3s, and other files for free for the first hour of the merged file, 10 times a day, with no sign-up. Longer merges run $0.01 a minute ($0.60 an hour), with no subscription — see pricing.
How do I merge MP3 files into one?
Add 2 to 20 files, move each up or down until the order is right, and download one merged file. MP3, WAV, M4A, and other formats can go in together.
Can I combine audio files on an iPhone?
Yes, right in your iPhone's browser: add the files, put them in order, and download the merged file. Android phones do it the same way.
Will the volume jump between files?
No. Make the files equally loud is on: each file is matched to the longest one, usually the main recording, so a quiet intro doesn't jump to a loud episode. Switch it off to keep each file's own level.
Can it crossfade from one file into the next?
Yes. Under More options, Crossfade blends each file into the next, by up to 5 seconds. With none, they play back to back.
Can I merge videos?
When every file is a video, you get a video back, with each picture scaled to the first video's size. Otherwise you get audio: in the first file's format when it's MP3, WAV, M4A, or FLAC, or else WAV. Pick another under More options.
Can I add audio to a video here?
No: merging plays files one after another. To put new sound on a video, use Replace audio in video. To play music under a voice at the same time, use Mix audio.
Can I merge more than 20 files?
Yes, in two steps: merge the first 20, then merge that file with the rest.
More tools
- EditorEdit audio and video right here.
- Cut audioTrim start, middle or end.
- Remove silenceCut out long pauses.
- Mix audioLayer voices and music.
- Audio enhancerMake any recording sound studio‑quality.
- Remove noiseClears the background, keeps your voice.
- Remove echoMake voices sound close.
- Transcribe audioSpeech to text, who said what.
- Text to SRTSync a script to audio.
- Remove filler wordsCut the ums and uhs.
For AI assistants and developers
Ask ChatGPT, Claude, or a coding agent to do this for you, or call it from your own code. When an agent's free result is cut short, it gives you a link to finish the whole file, no sign-up.
Show the free API call
curl -F file=@intro.mp3 -F file=@episode.mp3 -F file=@outro.mp3 https://audo.ai/api/try/join -D response.headers -o response.body