Period Calculator

Most cycles are between 21 and 35 days
Period Days
Fertile Window
Ovulation Day

Free Online Period Calculator

Track your menstrual cycle and predict future periods with our accurate period calculator.

How Our Period Calculator Works

Our period calculator uses your last menstrual date and cycle length to:

  • Predict your next period date
  • Calculate your fertile window
  • Determine ovulation days
  • Track menstrual cycles

Why Use PeriodCalc?

  • Easy-to-use period tracking tool
  • Visual calendar display
  • Accurate period predictions
  • Free and private to use

Understanding Your Menstrual Cycle

Period Phase

Your menstrual cycle begins on the first day of your period. Most periods last between 3-7 days, with the average being 5 days.

Ovulation Phase

Ovulation typically occurs 14 days before your next period. This is when you're most likely to conceive if you're trying to get pregnant.

Frequently Asked Questions

How accurate is the period calculator?

Our period calculator provides estimates based on your regular cycle. While most women have regular cycles, various factors can affect your actual period dates.

What is a normal menstrual cycle length?

A typical menstrual cycle lasts between 21-35 days, with 28 days being the average. However, every woman's cycle is unique.

Note: This period calculator is for informational purposes only. Consult with a healthcare provider for medical advice.
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