Multiple choice general knowledge How many Days in Mayan calendar 360 Days 365 Days 355 Days 345 Days Reveal answer Fill a bubble to check yourself A Correct answer Explanation The Mayan Haab' calendar had 360 days divided into 18 months of 20 days each, plus 5 unnamed 'wayeb' days considered unlucky outside the regular calendar. This 360-day cycle was used for agricultural and civic purposes.