Where on the web is iTunes version number

Apple aren't including the version number on the current iTunes download page https://www.apple.com/itunes/download/. The support document https://support.apple.com/kb/DL1814 normally shows the current version, albeit without the minor build number. At the moment it shows as 12.8 rather than the 12.6.0.150 which you would get from the about page in the application.

FWIW I maintain a list of iTunes installers in a user tip on this site which I generally update within a day of each new release.

tt2

What are you trying to establish? The "web" is massive and so your question is unrealistic. The version number you find will depend on where you look and therefore may be the current version or a previous one.

If you mean what is the current version of iTunes, it's 12.8. You can check within iTunes to see if you have the latest version, by clicking on Help/Check for Updates, which will (today) display this box:

If this doesn't help you, it might help if you explain why not and what you are trying to achieve.

Apart from the typo in 12.8.0.150. 😊

tt2