Audio conversion uses FFmpeg through the single-threaded @ffmpeg/core 0.12.10 build, licensed under GPL-2.0-or-later. FFmpeg. ffmpeg.wasm.
MP3 plays almost everywhere: old car stereos, smart speakers, cheap MP3 players, Windows Media Player, every phone and every editor. This audio to MP3 converter takes a sound file that one of your devices refuses to open and turns it into an MP3 that all of them can play. It works as an MP3 music converter for your song files and as a quick fix for voice recordings. For video files, use the video to MP3 converter instead.
How do I convert an audio file to MP3?
- Click Browse files or drag the audio file onto the converter.
- Pick the Audio quality. The page shows the estimated MP3 size.
- Click Convert to MP3 and wait a few seconds.
- Rename the file under Download name if you want, then click Download MP3.
Which audio formats does this MP3 audio converter accept?
This audio converter to MP3 accepts seven formats, split into two families. What you start with decides which bitrate makes sense.
| Format | Family | One minute of our test file | Page |
|---|---|---|---|
| WAV (16-bit, 44.1 kHz stereo) | Uncompressed | 10,584,078 bytes | WAV to MP3 |
| FLAC | Lossless | depends on the music | FLAC to MP3 |
| M4A (AAC, 128 kbps) | Lossy | 972,905 bytes | M4A to MP3 |
| AAC (raw ADTS, 128 kbps) | Lossy | 979,854 bytes | AAC to MP3 |
| OGG (Vorbis, quality 5) | Lossy | 730,036 bytes | OGG to MP3 |
| OPUS (mono, 32 kbps) | Lossy | 223,459 bytes | OPUS to MP3 |
| MP3 | Lossy | depends on its bitrate | This page |
We created each test file from the same 60-second clip with FFmpeg 7.1. Real files vary with their own settings; FLAC in particular shrinks more or less depending on the music.
What bitrate should I use for each audio format?
Match the bitrate to the quality of the source. Going higher than the source cannot add anything back.
- From WAV or FLAC: 256 or 320 kbps for music, because the source has full detail to keep.
- From M4A, AAC or OGG music: 192 or 256 kbps. The source is already compressed, so 320 kbps rarely helps.
- From OPUS voice notes and any speech: 128 kbps, the smallest option here.
- From another MP3: keep the same bitrate or go lower to save space. Raising it only makes the file bigger.
Why can my MP3 be bigger than the original audio?
Because some formats are more efficient than MP3. Opus and AAC sound good at low bitrates, and MP3 needs more data for the same result. In our test, a 32 kbps Opus voice note of one minute weighed 223,459 bytes, and its MP3 at 128 kbps weighed 960,931 bytes, more than four times as much. You convert for compatibility, not to save space. To save space, convert from WAV or FLAC, where MP3 is many times smaller.
Is an MP3 music converter bad for sound quality?
No, if you use a sensible bitrate. Every conversion to MP3 is lossy, but from a lossless file at 256 or 320 kbps most listeners cannot tell the difference. The quality loss adds up when you convert lossy to lossy several times, so always start from the best copy you have and keep the original.
When should I keep the original format?
- Keep WAV or FLAC as your archive. Make MP3 copies for your phone and car.
- Keep M4A or OGG if every device you use already plays them. Converting would only cost a little quality.
- Convert to MP3 when a player, website, editor or person you are sending to needs MP3.
What this audio converter does not do
It converts one file at a time, up to 150 MB, and it does not download audio from links or streaming services. It has no tag editor, trimming or volume tools. For any file type, including video, see the main MP3 converter.
Frequently asked questions about audio to MP3
What is the best free audio to MP3 converter?
One that converts the file on your device, lets you choose up to 320 kbps and asks for no install or sign-up. That is how this page works.
Do I lose quality when I convert audio to MP3?
A little, because MP3 is lossy. From WAV or FLAC at 256 or 320 kbps the difference is very hard to hear.
Is my audio file uploaded?
No. The conversion runs in your browser, and the file stays on your device.
Can I convert MP3 to MP3 at a higher bitrate?
You can, but it will not sound better. The detail removed by the first encoding does not come back.
Which audio formats can I convert?
WAV, FLAC, M4A, AAC, OGG, OPUS and MP3, up to 150 MB per file.
Can I convert music from Spotify or Apple Music?
No. Streaming apps do not give you audio files to convert, and this page does not download anything. Use files you own.
Convert your audio to MP3
Choose a WAV, FLAC, M4A, AAC, OGG or OPUS file, pick the quality and download the MP3.
More audio converters
- WAV to MP3: shrink uncompressed recordings.
- FLAC to MP3: lossless music for any player.
- M4A to MP3: iPhone voice memos and iTunes files.
- OGG to MP3 · OPUS to MP3 · AAC to MP3
- Video to MP3 converter: MP4, MOV, WEBM, MKV and MPEG.
- Guide: How to choose the best MP3 converter