The Period Date Calculator is a simple tool designed to predict the next date of your menstrual period. It uses the start date of your last period and the average length of your cycle to calculate the upcoming period date.

Period Date Calculator

Calculate your next period date with ease.

Next Period Date:

How to Use the Calculator

  1. Enter Last Period Date: Select the first day of your last menstrual period using the calendar input.
  2. Enter Cycle Length: Input the average length of your menstrual cycle in days (28 is the common average).
  3. Calculate: Click “Calculate” to see the predicted start date of your next period.


  • Example 1: Last Period: January 1, 28-Day Cycle: Next Period: January 29
  • Example 2: Last Period: February 1, 30-Day Cycle: Next Period: March 3
  • Example 3: Last Period: March 1, 26-Day Cycle: Next Period: March 27

Period Next Date Online Calculator

Additional Information

Understand that the calculator provides an estimate based on the information you provide. Cycle lengths can vary, and tracking over several months provides more accuracy. This tool is not a substitute for medical advice. For any concerns or irregularities, consult a healthcare provider.