How much will a two dollar bill be worth in 30 years?

Answer 1

No one knows specifically what ANY item will be worth in 30 months, let alone 30 years.

However if you're referring to modern $2 bills (1976 or later) there have been so many printed that any found in circulation are unlikely to increase in value. Uncirculated ones will probably increase but it's anyone's guess by what amount. If those of us interested in coins and currency could forecast that far into the future we'd be buying and selling like crazy and retiring early!