All Tools
1049+ free tools

Ovulation Calculator

Find your ovulation date and fertile window based on your last period and cycle length, plus predictions for your next cycle.

Your details

Count from the first day of one period to the first day of the next.

Your fertile window
Predicted ovulation date
Thu, Oct 1
In 6 days
Most fertile days
Sat, Sep 26 – Fri, Oct 2
Sperm can survive up to 5 days — the 5 days before ovulation + ovulation day are your fertile window.
Thu, Oct 15
Next period ≈
Thu, Oct 29
Following ovulation
Thu, Nov 12
Following period
Cycle timeline
Day 1 (LMP)Day 28 (next period)
PeriodFertile windowOvulation
How it works
Ovulation = next period − 14 days. Most reliable for regular cycles.

Related health tools

Calorie Calculator
Calculate daily calorie needs (TDEE) based on activity level
Macro Calculator
Split calories into protein, carbs, and fat by goal (cut/maintain/bulk)
Water Intake Calculator
Daily water requirement based on weight, activity, and climate
Ideal Weight Calculator
Ideal body weight using Devine, Robinson, Hamwi, and Miller formulas