Source: https://mactoolbox.app/glossary/mp3

# What is MP3?

By Nikhil Barik · Published November 3, 2026

## Quick answer

MP3 is a lossy audio format that plays on nearly every device. File size depends mainly on the bitrate you choose.

## What it is

MP3 removes sounds that are hard to hear to make files much smaller than WAV. At 128 kbps speech sounds fine, and music is often kept at 192 to 320 kbps.

## Why it matters on a Mac

Apple devices commonly use AAC in M4A, but MP3 is accepted by more players, cars and old devices.

## How to check it on macOS

Select the file in Finder and press Command-I, or drop it into Media Info in Toolbox to see its bitrate and sample rate.

## How Toolbox handles it

Convert Audio writes MP3, M4A, WAV, FLAC or AIFF. Extract Audio pulls a video's sound out as MP3, M4A, WAV or FLAC. Both let you pick a bitrate from 128 to 320 kbps for MP3 and M4A.

## Frequently asked questions

**Is MP3 or M4A better?**

M4A (AAC) often sounds better at the same bitrate. MP3 is more widely supported.

**Can I get lost quality back?**

No. Converting from MP3 to WAV does not restore detail.

**What bitrate is best for music?**

192 to 320 kbps.

## Tools mentioned

- [**Convert Audio**: Change audio files to MP3, M4A, WAV, FLAC or AIFF.](https://mactoolbox.app/convert-audio-to-mp3-mac)
- [**Extract Audio**: Save the soundtrack of a video as an audio file.](https://mactoolbox.app/extract-audio-from-video-mac)

## Keep reading

- [Convert Audio](https://mactoolbox.app/convert-audio-to-mp3-mac)
- [Extract Audio](https://mactoolbox.app/extract-audio-from-video-mac)
- [Bitrate](https://mactoolbox.app/glossary/bitrate)
- [Lossless vs lossy](https://mactoolbox.app/glossary/lossless-vs-lossy)