The Badi calendar is solar and geometrically simple by design: nineteen months of nineteen days each give three hundred sixty one days, closed by Ayyam-i-Ha, four intercalary days extended to five in a leap year, so the count reaches three hundred sixty five or three hundred sixty six and the calendar tracks the true solar year without ever needing a corrective month. Each of the nineteen months, and each of the nineteen days within a month, carries the name of an attribute of God: Splendor, Glory, Beauty, Grandeur, Light, Mercy and so on, so the calendar itself is a devotional recitation rather than a neutral grid. A given date can be read as, for instance, the day of Mercy in the month of Might.
The year opens at Naw-Ruz, the spring equinox, a choice inherited from the older Iranian solar calendars this reckoning replaced for Baha'i purposes. Since 2015 the Universal House of Justice has fixed Naw-Ruz to the astronomically determined equinox at the meridian of Tehran, so its Gregorian date can fall on the twentieth or twenty first of March depending on the year, rather than being pinned to a single civil date. The nineteen day month named Ala, Loftiness, is the last of the year and is preceded immediately by Ayyam-i-Ha, so the intercalary days function as a hinge between ordinary time and the fast that follows rather than a stray correction tucked away at the calendar's edge.