The birthday calendar is a dual monthly calendar and twelve-month chart. The calendar is perpetual in that it is not designated for any particular time period. The monthly calendar displays a month, either from a single use calendar or by filling in a month grid disposed on a dry-erase board with erasable ink. The chart is a grid used to permanently record and display birth dates and other annual dates such as anniversaries and holidays. The chart displays columns intersected by rows. The columns are grouped in twelve sets of two having a month column adjacent to a year column. The rows display the dates of each month down the left side of the chart, numbered from 1 31. An event is recorded in the chart by writing the event's name in the appropriate month and date space and the year in the adjacent year space.