This educational calculator uses finalized 2023 CDC state rates for chlamydia, gonorrhea, and primary/secondary syphilis, then applies broad age-band multipliers. It estimates reported-rate burden, not personal diagnostic probability or exact single-exposure risk.
A state rate is not the same as the chance of acquiring an STI from one sexual exposure. Single-exposure risk depends on whether the partner is infected, exposure type, anatomic site, condom use, PrEP, vaccination status, symptoms, treatment history, and local sexual network. Testing is recommended after a concerning exposure regardless of the state tier.