About this tool
From planning to the birth, three questions come back often: when the next period and the fertile window are, how many weeks the pregnancy has and when the baby is due, and whether the weight gain is on track. Here the three live together. Choose what you want to calculate at the top. The date of your last period typed in the cycle goes along to the weeks of pregnancy, and everything is worked out in your browser: nothing is sent to a server or put in the address. These are estimates, not a substitute for prenatal care.
How to use it
- 1 Choose at the top: cycle, weeks of pregnancy or weight gain.
- 2 Type the first day of your last period (or the ultrasound date), or your weight before pregnancy and height.
- 3 Read the result: next periods and fertile days, weeks and due date, or the healthy gain for this week.
- 4 Switch at any time: the last period follows you, and each one keeps what you typed while the page is open.
Frequently asked questions
Are my dates and weight saved or sent anywhere?
No. They stay in your browser. They are not sent to a server, not saved and not put in the page address.
Do the menstrual cycle, gestational age and pregnancy weight gain pages still exist?
Yes. Each one opens this same page on its own calculator.
How accurate are these dates?
They follow the usual medical rules (Naegele's rule for the due date, ovulation about 14 days before the next period), so they are averages. Cycles vary, and an early ultrasound gives a more precise date than the last period.
Where is the maternity leave calculator?
It stays with the work calculators, because it counts days of leave and job security rather than weeks of pregnancy.
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