Period Calculator
HealthTracks menstrual cycles and predicts the start date of future periods.
How to use this calculator
Start with your values, or try a preset.
Enter Average Cycle Length (days), Start Date of Last Period, and Number of Cycles to Predict in the units shown.
Read Predicted Start Date of Next Period, Period Start Date 1, Period Start Date 2, Period Start Date 3, Period Start Date 4, Period Start Date 5, and Period Start Date 6 in the results panel. Results update as you change the inputs.
Choose a preset to load an example, then adjust the values for your situation.
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Calculates the average arterial pressure during a single cardiac cycle. MAP is considered a better indicator of perfusion to vital organs than systolic blood pressure.
Use the result as an estimate and confirm any medical decisions with a qualified professional.