1
general::
Also, that figures. It's (or that's) reasonable; it makes sense. For example, Hanging it upside down sounds like a weird idea, but it figures, or It figures that they won't be coming this year, or So she's complaining again; that figures. This idiom alludes to reckoning up numbers. [Colloquial; mid-1900s]
American Heritage Idioms
2
general::
Phrase(s): It figures.
It makes sense.; It confirms what one might have guessed.; I’m not surprised. • Bob: Tom was the one who broke the window. Bill: It figures. He’s very careless. • Ann: Mary was the last one to arrive. Sally: It figures. She’s always late.
McGrawhill's American Idioms And Phrasal Verbs