Measles Incubation Calculator

When using this calculator, it is important to understand the biological timeline of the virus:

  • Incubation Period: This is the “silent” phase. You generally won’t feel sick for the first 7 to 14 days.

  • The Prodromal Phase: Around day 10, the “3 C’s” usually appear: Cough, Coryza (runny nose), and Conjunctivitis (pink eye), accompanied by a high fever.

  • Koplik Spots: 2 to 3 days after symptoms start, tiny white spots may appear inside the mouth.

  • The Rash: This typically breaks out 3 to 5 days after the first symptoms begin (roughly 14 days after exposure). It usually starts at the hairline and spreads downward to the feet.