Best Free Audio Converter

How it works

1. Upload. Choose an audio file (up to 100 MB).
2. Pick a format. Select MP3, WAV, OGG, M4A, FLAC or Opus.
3. Download. The converted audio downloads automatically; nothing is stored.

About this tool

Audio Converter changes an audio file from one format to another: MP3 for universal playback, WAV or FLAC for lossless quality, or OGG, M4A and Opus for efficient modern encoding. It runs server-side with ffmpeg under a size cap and a hard time limit, so the free tier stays responsive. Whether you need a smaller MP3 to share or a lossless WAV for editing, you pick the target and the tool handles the encoding. No watermark, no signup, and your file is deleted right after conversion.

What people use it for

• Convert a WAV to MP3 to make it smaller
• Get a lossless WAV or FLAC for editing
• Convert to M4A or Opus for efficient streaming
• Change an audio file’s format for an app that needs it

Developer API

Automate this tool from your own code. Send a POST request to the endpoint below and get the same result the web tool produces. It is rate-limited per IP and needs no signup — API keys for higher limits are coming.

• cURL
• Python
• JavaScript

curl -X POST https://best.free/api/tools/audio-converter/ \
  -F 'file=@track.wav' \
  -F 'format=mp3' \
  -o audio.mp3

import requests

files = {"file": open("track.wav", "rb")}
data = {"format": "mp3"}

r = requests.post("https://best.free/api/tools/audio-converter/", files=files, data=data)
with open("audio.mp3", "wb") as out:
    out.write(r.content)

const fd = new FormData();
fd.append("file", fileInput.files[0]);
fd.append("format", "mp3");

const r = await fetch("https://best.free/api/tools/audio-converter/", { method: "POST", body: fd });
const blob = await r.blob();  // the audio.mp3

Response: The converted audio file.

Frequently asked questions