Home › Ovulation Calculator
Ovulation Calculator (Fertile Window)
Advertisement
…
How it is calculated
- Ovulation ≈ next period − luteal phase (typically 14 days)
- Fertile window = 5 days before ovulation + ovulation day
Estimates only — not medical advice.
FAQ
How accurate is an ovulation calculator?
It assumes regular cycles, so it is a starting estimate. Ovulation can shift by several days month to month; LH test strips, basal body temperature or cervical-mucus tracking confirm it.
When am I most fertile?
In the 2–3 days up to and including ovulation, because sperm can survive up to about 5 days and the egg about 12–24 hours.
Can I use this as contraception?
No. Calendar estimates are not reliable birth control. Talk to a healthcare provider about contraception.
More health calculators
- BMI Calculator
- Calorie Calculator (TDEE & BMR)
- BMR Calculator (Basal Metabolic Rate)
- Body Fat Calculator (US Navy Method)
- Ideal Weight Calculator
- Water Intake Calculator
- Macro Calculator (Protein, Carbs, Fat)
- Running Pace Calculator
- One Rep Max Calculator (1RM)
- Sleep Calculator (Bedtime & Wake-up)
- Pregnancy Due Date Calculator
- Protein Intake Calculator
- Calories Burned Calculator (by Activity)
- Metric BMI chart (cm/kg)
- Ideal weight by height
Advertisement
Free calculator by BodyCalc