Audio Converter

How to convert audio

1. 1

   Choose a file

   Pick or drop one MP3, WAV, M4A (AAC), Ogg or FLAC file. Play it to check it is the right one.

2. 2

   Choose the format

   Select MP3, WAV or FLAC. For MP3 pick 128, 192 or 320 kbps. The output settings are shown before you convert.

3. 3

   Convert and download

   Press Convert audio, play the result, check its real format and size, then download it.

What to know

• What your browser can read. Files are decoded by your browser’s own audio decoders: MP3, WAV (PCM and 32-bit float), M4A with AAC-LC, Ogg Vorbis or Opus, and FLAC. A format your browser cannot decode (for example Ogg in older Safari) is rejected with a message. Files with video, several audio tracks, copy protection, more than two channels or other codecs are refused rather than guessed at.
• MP3 is made with LAME. MP3 is written at a constant bitrate of 128, 192 or 320 kbps by the LAME encoder, compiled to WebAssembly and loaded from this site only when you convert. Mono stays mono and stereo stays stereo. MP3 can only hold certain sample rates, so a 96 kHz file becomes 48 kHz and an 88.2 kHz file 44.1 kHz; the page tells you before you convert.
• WAV is 16-bit PCM. WAV output is uncompressed 16-bit little-endian PCM at your file’s sample rate, with no dither. It is large: about 10 MB per minute for 44.1 kHz stereo. A 24-bit or float source is rounded to 16 bits.
• FLAC is lossless, at 16 bits. FLAC output is compressed without further loss from the 16-bit decoded audio, using libFLAC compiled to WebAssembly. It is smaller than WAV and adds no further loss.
• A higher bitrate does not add quality. Converting a 128 kbps MP3 to 320 kbps makes a larger file, not a better one, and converting between lossy formats loses a little more each time. MP3, M4A or Ogg to WAV or FLAC keeps how it sounds now; it cannot restore what compression removed.
• Same format, same settings. If your file is already in the format and settings you picked, the tool says so and offers your original instead of pretending a conversion helped. You can still convert anyway.
• Not a bit-for-bit copy. Your browser decodes the file first, and browsers scale 16-bit samples slightly differently, so even WAV to WAV can differ by one step in the last bit (about −90 dB, inaudible). Title, artist, cover art and other tags are not carried over to the new file.

Limits

largest audio file

100 MB

longest audio

20 minutes

largest result

320 MB

Audio is decoded to 32-bit floating point in memory while you work (about 21 MB per minute of 44.1 kHz stereo), so very long or high sample rate files can run out of memory on small devices. The finished file is also held in memory until you download it. Cancel stops the work at once and keeps nothing.

Frequently asked questions