MP3 Encoder
Convert WAV, OGG, M4A, FLAC, or other audio files to a real, compressed MP3 — encoded entirely in your browser using a JavaScript port of the LAME encoder. Files up to 50 MB are never uploaded to a server.
Click to upload or drag and drop
WAV, OGG, M4A, FLAC, or other common audio formats
How this differs from the Audio Converter
The site's Audio Converter can only output uncompressed WAV, since your browser can decode compressed audio but can't re-encode it without a dedicated encoder library. This tool adds that missing piece specifically for MP3 — the most widely compatible compressed format — using a JavaScript port of LAME, the same encoder most desktop MP3-encoding software is built on.
Choosing a bitrate
128 kbps is a reasonable minimum for spoken word or casual listening; 192 kbps is a solid, broadly recommended balance for music; 320 kbps is the highest standard MP3 bitrate and close to indistinguishable from the source for most listeners, at the cost of a larger file. Changing the bitrate re-encodes the same decoded audio instantly, without needing to re-upload the file.
Frequently asked questions
How is this different from the Audio Converter tool?
The Audio Converter can only output uncompressed WAV, since browsers don't include a built-in MP3 encoder. This tool adds a dedicated JavaScript MP3 encoder (a port of LAME) specifically to produce real, compressed MP3 output.
Is the quality as good as a desktop MP3 encoder?
Yes — this uses a JavaScript port of LAME, the same encoder most desktop MP3 software is built on, not a simplified or lower-quality substitute.
Why does re-encoding an existing MP3 lose quality?
MP3 is a lossy format — some audio detail is permanently discarded during encoding to shrink the file. Decoding an MP3 and re-encoding it (for example, to change the bitrate) compounds that loss a second time, known as generation loss. For the best result, encode from the original uncompressed or lossless source when you have it.