Why doesn't the number of data in the header of the wav file match the real value when recording sound in windows sound recorder?

Question

Qt

When recording from a microphone with a standard windows program, why does the number of data in the header of a wav file not match the real value? For example, the value of data in the header is 13654786 bytes, and the size of the wav file is 47Kb. The file plays normally.

Answer 1

See format. Most likely, wav is compressed.