More info on JR Tokyo Wide pass

I read the value and coverge of JR Tokyo wide pass as japan guide...it does not mention regards its value if I want to travel to Yokohama as well...Thank you.

Are you going to use it just to travel to Yokohama? If so, that would be a waste of money.

The webpage isn't going to detail the value perfectly for every individual itinerary. You could find out for yourself if the pass would be cost-effective for you, by looking up the fares on Hyperdia (hyperdia.com/en), then comparing them to the cost of the pass.

I want to travel to Yokohama as well
What other places are you planning to use the Pass for?

What?
Just Google MAP knows.
https://goo.gl/maps/1VZQHMWHwU82

If non "JR" small green icon execpt Fujikyu and Izukyu
or "Tokaido-Sanyo Shinkansen" is NOT covered.
https://goo.gl/maps/SaLrBgT7Nfp
https://goo.gl/maps/TYNYpYe7Y8J2
https://goo.gl/maps/DU54pcbf3hw

You had to read this first, but.
http://www.japan-guide.com/e/e2323.html

And Pass official web is here.
http://www.jreast.co.jp/e/tokyowidepass/index.html
www.japan-guide is one of travel info web.
No official related/belonging transportation/travel agency companies.

Forgot other Private railways as exception.
http://www.jreast.co.jp/e/tokyowidepass/index.html
"Valid Train Routes"