🤰Pregnancy & Fertility Calculators

Pregnancy and fertility calculators — due date, fertile days, ovulation

This wizard combines two pregnancy and fertility calculators: due date calculator and fertile days and ovulation calculator. Everything runs locally in your browser — no registration, no ads, no data sent to a server.

Pregnancy calculator computes the estimated due date (EDD) using Naegele's rule and estimates the current week of pregnancy. Fertile days and ovulation calculator determines the fertility window and approximate ovulation date based on menstrual cycle length.

Important note: results from both calculators are indicative only and do not constitute a medical diagnosis. The fertile days calculator is not a method of contraception and does not guarantee conception. Always consult a doctor or midwife regarding pregnancy, fertility, and contraception.

Indicative results

All calculations are performed locally in your browser — no data leaves your device. Results are indicative and do not replace advice from a doctor or midwife. Always consult a specialist before making decisions about reproductive health.

Frequently asked questions

How is the estimated due date calculated?

The most popular method is Naegele's rule: 280 days (40 weeks) are added to the date of the last menstrual period. The due date is an estimate — only about 5% of babies are born exactly on the predicted day. The actual date depends on many factors and should be confirmed by a doctor via ultrasound.

When do fertile days and ovulation occur?

With a regular cycle, ovulation typically occurs about 14 days before the next period. Fertile days are usually the 5 days before ovulation and ovulation day itself. The calculator gives an indicative result based on cycle length — the actual ovulation date may differ. These calculations are not a method of contraception.

Does the pregnancy and fertile days calculator replace a visit to the doctor?

No. Results are purely indicative and do not constitute a medical diagnosis or a method of contraception. The fertile days calculator does not guarantee effective protection against pregnancy or increase the certainty of conception. Any health decisions related to pregnancy and fertility should be made after consulting a doctor or midwife.