Pregnancy Due Date & Ovulation Calculator

● Launching

Estimate your due date, fertile window and pregnancy week — free and instant.

This tool is built and in its launch checks — it will be live at due-date-calculator.pages.dev shortly.

About this tool

Two health calculators on one site: a pregnancy due date calculator (from your last period, conception date or ultrasound) that shows your current week, trimester and milestones, and an ovulation calculator that finds your fertile window and best days to conceive. Estimates only — always confirm with your doctor or midwife.

Searches this tool answers

People find this tool by searching for “pregnancy due date calculator”. Related searches it is built for:

ovulation calculator fertile window
when is my due date by lmp
how many weeks pregnant am i calculator

Frequently asked questions

How is a due date calculated?

By Naegele's rule: 280 days (40 weeks) from the first day of your last menstrual period. Only about 1 in 20 babies arrive on the exact date, so treat it as an estimate.

What is my fertile window?

The five days before ovulation plus ovulation day itself. The ovulation calculator works it out from your last period and average cycle length.

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Period Calculator — Predict your next three periods and your fertile window — private, nothing stored.
Water Intake Calculator — How much water you actually need — by weight, activity, climate and pregnancy.