Upload two audio files, adjust the volume of the second track (dB), and mix them into a single track.

Click or drag to upload
Click or drag to upload

How to Mix Audio Tracks Online – Free Audio Mixer Guide

Learn to mix two audio files online free. Combine background music with voiceover, blend two songs, or create remixes. Control the volume of the second track from -30dB to +10dB. Supports MP3, WAV, AAC, FLAC, OGG and more. No signup needed.

How Does Audio Mixing Work?

Mixing combines two audio sources into one blended track. Our tool uses FFmpeg's amix filter with volume adjustment. You can increase or decrease the second track's volume (in dB) before blending. The output duration matches the longer input, while the shorter track plays once and stops (no looping).

Step‑by‑Step to Mix Audio

  1. Upload your main audio (e.g., voiceover).
  2. Upload the second audio (e.g., background music).
  3. Adjust the volume of the second track using the slider (-30dB to +10dB).
  4. Click 'Mix Tracks' – processing happens in your browser.
  5. Preview and download the mixed audio file.

Frequently Asked Questions

1. What happens if the two files have different lengths?
The output length is the longer of the two. The shorter track stops when it ends, and only the longer continues (no repetition).
2. Can I adjust the volume of the first track too?
Currently only the second track's volume is adjustable. For full mixing, you may need a DAW, but this tool is great for background music + voice.
3. What audio formats are supported?
All common formats: MP3, WAV, AAC, FLAC, OGG, Opus, M4A, etc.
4. Does mixing reduce quality?
We re-encode the final output to 192kbps MP3, which is transparent for most uses. For lossless mixing, use a professional editor.
5. Is my audio uploaded to a server?
No. All processing uses FFmpeg.wasm in your browser – files never leave your device.

Mix Audio Perfectly for Podcasts, Videos, and Music

Mixing audio is a common task for podcasters adding intro music, YouTubers adding background sound, or musicians creating simple remixes. Our free online tool makes it easy: upload two files, adjust volume, and download the blend. No signup, no watermarks, completely private.