file size of audio file after exporting

Why does the size of my audio file remain as large as the unedited version after I export it? For example, I export a 25 second clip from a 3 minute audio file and the size is exactly the same. What could I be doing wrong in the process? Thanks for your help.

It depends on the format… Compressed formats are “rated” in kbps (kilo_bits_ per second). Uncompressed files (i.e. WAV) depend on the number of samples (i.e. 44.1kHz - 44,100 samples per second) times the bit depth times the number of channels. There are 8 bits in a byte, so an uncompressed 44.1khz 16-bit stereo file needs 176,400 bytes per second, or about 10MB per minute.

If you started out with a highly compressed MP3 or A4F and edited down to a small fraction, but exported it as an uncompressed WAV, the edit could actually be bigger. You also need to know that Audacity does not edit MP3. It converts MP3 to a very high quality internal format and edits that. It then exports a completely new MP3 using the specifications of your choice. That, too could give you a larger file after the edit.

If you’re only splitting off unused segments of an MP3, you may be far better off with one of the MP3 editors like MP3Splt. They don’t have to make new all new files.