zerouploads

WAV to MP3 Converter

Turn a WAV into an MP3 a quarter to a tenth of the size, at the bitrate you pick. Nothing is uploaded.

  • Unlimited
  • No signup
  • Private
  • Works offline

Convert an audio file

44.1 kHz is CD quality and the safe pick. A lower rate cuts the treble, and only makes WAV and FLAC files smaller.

Bitrate
Audio options
Commandffmpeg -i input.mp4 -vn -af loudnorm=I=-14:TP=-1.5:LRA=11 -c:a libmp3lame -b:a 256k -map_metadata 0 audio.mp3
Choose an audio file to start

How it works

  1. 01

    Add the WAV

    Drop it here or choose it. Nothing is uploaded, so there is no upload wait.

  2. 02

    Pick a bitrate

    192 kbps suits most things. 320 kbps is the most MP3 can carry.

  3. 03

    Save the MP3

    Download it when the bar fills. You can pick another format first.

Why a WAV is so much bigger

A WAV stores every sample as a raw number, with nothing thrown away and nothing packed. CD-quality stereo works out at about 10 MB a minute, so an hour-long interview is over 600 MB.

An MP3 throws away what is hardest to hear and packs the rest. At 192 kbps the same minute is about 1.4 MB, roughly a seventh of the size. On speech, few people can tell the two apart.

You cannot undo this. The detail an MP3 drops is gone, and saving it back to WAV later gives you a large file with the small file's audio. Keep the WAV if it is your master copy.

Input
WAV, AIFF, FLAC, M4A, OGG and the usual video files. One at a time.
Output
MP3, AAC, WAV, FLAC or OGG, at the bitrate you choose.
Size
No cap and no queue. Your own memory is the only limit, because nothing is uploaded.
Extras
Even out the loudness to -14 LUFS, trim silence at the start, and copy the title and artist tags.

Frequently asked questions

Is my recording uploaded?
No. The encoding happens in this tab, on your own machine. Nothing is sent, so there is no upload wait and nothing to delete afterwards.
How much smaller will the MP3 be?
At 192 kbps, about a seventh of a CD-quality WAV. A 500 MB recording lands near 70 MB. The page shows an estimate before you convert.
Will it sound worse?
A little, and on speech few people hear it. MP3 drops what is hardest to hear. Pick 256 or 320 kbps for music if you want to be sure.
Can I turn the MP3 back into a WAV?
You can make a WAV from it, but the detail MP3 removed does not come back. You would get a large file holding the small file's audio.
Is there a size limit?
No fixed one. The tool loads the whole file into memory first, so the limit is the memory your browser has spare.
Can I convert several at once?
No. It converts one file at a time, because the whole file is held in memory while it is encoded.

More audio tools

JSON FormatterFormat, validate and minify JSON in the browser. Errors are reported with a line and column, not a stack trace.PNG to WebPConvert PNG images to WebP in your browser. Batch any number of files, choose quality, keep transparency.Word CounterCount words, characters, sentences and paragraphs, with reading time and keyword density.Age CalculatorWork out exact age in years, months and days between any two dates, plus totals and the next birthday.AVIF to JPGConvert AVIF images to JPG in your browser. AVIF packs tighter than JPG, so expect a bigger file, and clear parts take the colour you pick.Base64 DecodeDecode Base64 back to text or a file. Handles URL-safe input, missing padding and embedded line breaks.
Browse all audio tools