Convert WAV to MP3

I accidentally recorded a few audio files in .WAV file format instead ofMP3. Is there an easy way to convert?

If the .WAV file was recorded using MPEG compression, simply rename the file to use an .MP3 file extension, and the file will play in the vast majority of MP3 player programs and MP3 devices.

Why does this work?

MP3 was designed to be a streaming format, and part of that design is to deliver the audio data in sections (called frames) and have a way to synch up to the next frame in case of loss of data, network problems, or starting playback in the middle of a stream. MP3 files often include non-audio data,called tags, at the beginning or end of the file, and player software is already designed to skip over tags to find the beginning of the first frame of audio.

Here is a conceptual schematic of one MP3 file with no tags:

<mp3 frame>
<mp3 frame>
<mp3 frame>

The WAV file format has a few extra bytes at the beginning of the file, butMP3 players will usually ignore bytes at the beginning of a file they don’t understand. Refer to this conceptual schematic of one WAV file:

‘RIFF’ <4 length bytes>
‘WAVE’
‘ fmt’ <4 length bytes> <format data>
‘data’ <4 length bytes>
<mp3 frame>
<mp3 frame>
<mp3 frame>

My WAV file does not use MPEG compression. Now what do I do?

If you are running under Windows XP or earlier, open up the Sound Recorder accessory by clicking Start-> All Programs-> Accessories->Entertainment-> Sound Recorder. (The exact click path may vary with your version of Windows.) In the program, open up your WAV file, and click menu File-> Save As, enter a new file name, and click the Change button at the bottom of the file dialog.

save as dialog

In the “Sound Selection” popup dialog, select MPEG as the Format, and select the bit rate you desire as Attributes:

sound selection dialog

Click OK to begin converting:

converting dialog

Now you have a .WAV file which uses MPEG compression, and you can rename to an MP3 file extension. Test the file by playing with Media Player, or other MP3player software.