Chris knows his shit

And remember. No matter what the stripper tells you, there is no sex in the champagne room.

Top tip: not only is asking to see her ID rude, they don't matter given how easily they are faked.
Look for laugh lines, crows feet (both hot, IMO) and at her hands. The only way to be even remotely sure.
Alternatively, hang out in places where the clientele is known to be older.

In other words, women can't be trusted. Don't believe anything that comes out of her mouth.

:( but what if you really are 25 and look 16

And if she looks 20 and is actually 16......