Once you’ve done this, open up your wishlist and there should be an amount listed at the top that tallies up the number of V-Bucks your inventory is worth. Since there isn’t a way to add the skins and items that come as part of the game’s battle pass, you should add 950 V-Buck to this total for every Battle Pass you’ve had.
Since 1,000 V-Bucks can be bought for $7.99, all you have to do is some simple math to know how much your account is worth.
Source: https://www.distractify.com/p/how-much-is-my-fortnite-account-worth