Ovulation Calculator — Free Fertility & Cycle Tracker

⚕️ Medical Disclaimer: This calculator is for informational purposes only. Cycle predictions are estimates based on average patterns and may not reflect your individual biology. Always consult a qualified healthcare provider for personalized medical advice, diagnosis, or treatment.

🔒 Privacy Policy

We do not collect, store, or transmit any personal health data. All calculations are performed locally in your browser using JavaScript. No cookies are used, no analytics or tracking scripts are loaded, and no network requests are made for any calculations. This tool works entirely offline once the page has loaded. Your health information stays completely private — always.

Frequently Asked Questions

When am I most fertile?

You are most fertile during your fertile window, which spans approximately 5 days before ovulation and the day of ovulation itself. For a 28-day cycle, this is typically days 10-16.

How do I calculate my ovulation date?

Ovulation typically occurs 14 days before your next period. Enter the first day of your last period and your average cycle length into our calculator for a personalized prediction.

How long does ovulation last?

The egg is viable for 12-24 hours after ovulation. However, sperm can survive 3-5 days in the reproductive tract, making the fertile window several days wide.

Can ovulation dates vary each month?

Yes — stress, illness, weight changes, and other factors can shift ovulation timing. This calculator provides an estimate based on average cycle patterns.

Is this calculator suitable for birth control?

No. This tool is for informational purposes only and is not reliable for contraception. Please consult a healthcare provider for birth control guidance.

📅 Enter Your Cycle Details

📋 Your Fertility Summary

Calendar Key

🛒 Fertility Essentials