Audio Converter
Convert audio to MP3, WAV, M4A, OGG, Opus or FLAC for free, right in your browser. Turn WAV, M4A or FLAC into MP3, or MP3 into WAV, choose the bitrate and convert a whole batch at once. Your files are never uploaded.
LAME MP3: plays everywhere.
Drop audio files or click to choose
MP3 · WAV · M4A/AAC · OGG · FLAC · OPUS · WebM · AIFF · multiple files OK
Files are processed on your device. The FFmpeg engine (~30 MB) is downloaded once from a CDN and then cached by your browser. Because ffmpeg.wasm keeps files in memory, very large files (over ~500 MB) may fail on phones or low-memory computers.
How to convert audio to MP3
- Add audio files. Drag MP3, WAV, M4A, AAC, OGG, FLAC, Opus, WebM or AIFF files onto the drop zone, or click it to choose them. You can add several files at once.
- Choose the output format. Pick MP3, WAV, M4A, OGG, Opus or FLAC. For lossy formats choose a bitrate (128 to 320 kbps, or VBR for MP3).
- Set optional audio settings. Optionally change the sample rate, convert stereo to mono, or turn on Normalize volume to even out loudness to -16 LUFS.
- Convert and download. Click Convert. Each file shows its own progress bar and a preview player. Download files one by one or click Download all.
Audio formats and bitrates explained
- MP3: plays on every device. 192 kbps is transparent for most music; 320 kbps is the maximum.
- M4A (AAC): Apple's default. Sounds better than MP3 at the same bitrate, so 128–192 kbps is plenty.
- OGG (Vorbis) and Opus: open formats used by games, Linux and the web. Opus is very efficient at low bitrates and always runs at 48 kHz.
- WAV: uncompressed 16-bit PCM. Large (about 10 MB per stereo minute) but accepted by every editor.
- FLAC: lossless compression. Same quality as WAV at roughly half the size.
Converting between lossy formats (for example M4A to MP3) re-encodes the audio, so pick a bitrate at least as high as the source. Converting a lossy file to WAV or FLAC does not restore lost detail.
Tips for better conversions
- Choose Mono for voice recordings and podcasts to halve the file size with no audible loss.
- Keep the original sample rate unless a device needs 44.1 kHz (CD, most players) or 48 kHz (video).
- Use Normalize volume when combining clips recorded at different levels.
- Video files work too: the converter takes the first audio track and ignores the picture.
Private audio conversion, no upload
The file is processed on your device; the FFmpeg engine (~30 MB) is downloaded once from a CDN and then cached by your browser. Nothing you convert is sent to a server, so it is safe for unreleased music, interviews and voice memos. Because ffmpeg.wasm keeps files in memory, very large files may fail on phones.
Frequently Asked Questions
How do I convert WAV to MP3?↓
Drop your WAV files onto the converter, select MP3, choose a bitrate (192 kbps is a good default, 320 kbps for maximum quality), and click Convert. Each file is encoded with the LAME MP3 encoder in your browser and can be downloaded right away.
Are my audio files uploaded to a server?↓
No. Conversion runs on your device with FFmpeg compiled to WebAssembly. Only the FFmpeg engine (about 30 MB) is downloaded once from a CDN; your audio files never leave your computer or phone.
Which MP3 bitrate should I choose?↓
128 kbps is fine for speech and podcasts, 192 kbps is transparent for most music, and 256 or 320 kbps is for archiving or critical listening. VBR (V2) adjusts the bitrate to the music and usually averages around 190 kbps with smaller files than 320 kbps.
Does converting MP3 to WAV or FLAC improve quality?↓
No. Converting a lossy file such as MP3 or M4A to WAV or FLAC keeps exactly the quality it already has; it only makes the file larger. Convert to WAV when an editor or device needs uncompressed audio.
What does Normalize volume do?↓
It applies EBU R128 loudness normalization so the output averages -16 LUFS with peaks below -1.5 dBTP. This makes quiet recordings louder and loud ones quieter, so a batch of files plays at a similar volume.
Is there a file size limit?↓
There is no fixed limit, but ffmpeg.wasm works inside a 2 GB browser memory space, so files over about 500 MB may fail, especially on phones. Typical songs, podcasts and recordings convert without problems.
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