Free Online Audio Converter
Convert audio files to MP3 or WAV with bitrate and quality controls.
Lower sample rates reduce size but also reduce high-frequency detail.
Load an audio file to see its properties and estimated output size.
Converted audio
ReadyAbout the Audio Converter
Audio files come in many containers and codecs, and not every device or app understands all of them. This converter reads an audio file with the Web Audio API and writes a fresh MP3 or WAV file that you can download. It is useful for turning a large WAV export into a smaller MP3, changing a high-resolution recording to a friendlier sample rate, or producing an uncompressed WAV for editing. Your file stays on your device.
Supported inputs
The tool accepts MP3, WAV, OGG, M4A, AAC, FLAC, and anything else your browser can decode. Chrome, Edge, Firefox, and Safari support slightly different codec sets, so a file that works in one browser may not work in another. The safest inputs are MP3, WAV, M4A/AAC, and OGG. If a file fails, try opening it in a media player and exporting it as WAV first.
Output settings explained
- MP3 bitrate: 128 kbps is compact and fine for speech, 192 kbps is a good default for music, and 320 kbps preserves the most detail.
- WAV: uncompressed 16-bit PCM. It is the largest option but avoids additional lossy encoding, which is helpful before editing or mastering.
- Sample rate: keeping the original avoids unnecessary processing. Converting to 44.1 kHz or 48 kHz matches common playback devices; 22.05 kHz and 16 kHz are suitable for voice recordings and podcasts.
How conversion works
After decoding, the tool optionally resamples the audio with an OfflineAudioContext. Resampling is
a proper audio operation rather than a header change, so the pitch and speed stay correct. MP3 encoding uses
the lamejs encoder and runs in small blocks so the page stays responsive and shows progress. WAV output is
written as a standard RIFF file with interleaved 16-bit samples. The result is a new file; your original file is
not changed.
Frequently asked questions
Does converting MP3 to WAV restore quality?
No. Converting a lossy MP3 to WAV preserves the audio exactly as it is in the MP3, including its limitations. WAV is useful for editing, not for recovering lost detail.
Why is the WAV file so much larger?
WAV stores every sample without compression. At 44.1 kHz stereo, one minute is about 10 MB, while a 192 kbps MP3 of the same audio is about 1.4 MB.
Can I convert multiple files at once?
This page converts one file at a time. Use the Audio Joiner if you want to combine several files into one track.