Period Calculator

Please enter a valid date
days
Please enter between 21-45 days
days
Please enter between 2-10 days
days
Please enter between 10-20 days

Your Cycle Overview

Next Period

-
Estimated start date

Ovulation

-
Most fertile day

Fertile Window

-
Best days to conceive

Luteal Phase

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Post-ovulation phase

Cycle Calendar

Cycle Phases

Menstrual Phase

Days 1-5: Shedding of uterine lining

Follicular Phase

Days 6-13: Follicles develop in ovaries

Ovulation

Day 14: Egg is released from ovary

Luteal Phase

Days 15-28: Uterine lining prepares for pregnancy

About This Period Calculator

Our Period Calculator helps you track your menstrual cycle using the original color scheme, with improved mobile responsiveness.

How it works: The calculator uses the first day of your last period and your average cycle length to estimate:

  • Your next period start date
  • Ovulation day (typically 14 days before next period)
  • Fertile window (5 days before ovulation)
  • Different phases of your menstrual cycle

Note: These are estimates only. Track your actual cycles for more accurate predictions.

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