How to get the real, internal Genre value (number)?

Support
1

As far as I know the Genre is internally encode as a simple number in a MP3 header.

MP3tag shows in the column "Genre" the corresponding Genre as full label text.

E.g. 145--->Pop

It works in Mp3tag. However in (other) audio players (on Android) I got some strange values as Genre. So would like to peek directly into header to get the real internal Genre value for further investigations.

How can I tell Mp3tag to show me this number (and not the interpretation)?

Are there differences between ID3v2.3 and ID3v1 Genre encodings?

2

MP3tag has no option to show the used number.
The number is only used for ID3V1 tags.

3

As @ohrenkino already wrote, Mp3tag can not show you the used number.

Here is a list with all fixed Genre names and associated numbers:
The first 80 official ones and also the Winamp extension: