How accurate is the due date?

The calculated due date is an estimate. Only about 5% of babies are born on their exact due date; most arrive within two weeks.

How is the due date calculated?

The standard method (Naegele's rule) adds 280 days (40 weeks) to the first day of your last menstrual period. This assumes a 28-day cycle with ovulation on day 14. Your doctor may adjust based on an ultrasound measurement.

What is a full-term pregnancy?

A full-term pregnancy is 39–40 weeks. Babies born at 37–38 weeks are 'early term', 41 weeks is 'late term', and 42+ weeks is 'post-term'. The calculator displays your trimester milestones alongside the due date.

Pregnancy Due Date CalculatorFree Online Health Tool

Pregnancy Due Date Calculator is a free online health tool. Calculate your estimated due date and track your pregnancy progress week by week.

Your Information

Enter your last menstrual period date

First Day of Last Period

Average Cycle Length (days)

Your Due Date

Estimated delivery date

Enter your last period date to calculate your due date

100% Private

Instant

Any Device

Free Forever

Pregnancy Due Date Calculator is part of our health tools collection and is built to help you finish common tasks quickly without installing extra software. The workflow is intentionally simple: open the tool, add your input, adjust options if needed, and get results immediately in your browser. Whether you are working on a quick personal task or a repetitive professional workflow, this page is designed to save time and reduce friction.

Unlike many web utilities that require account creation or server-side uploads, this tool focuses on speed, clarity, and privacy-first processing. You can test, iterate, and refine your output in seconds, then export or copy the final result when you are satisfied. The step-by-step guidance, examples, and related tools below are included so you can move from one task to the next without breaking your workflow.

If you use Pregnancy Due Date Calculator regularly, it can become a reliable part of your daily toolkit for content work, development, design, analysis, or productivity. Keep this page bookmarked, compare outputs with similar tools when needed, and revisit the "How to use" section for faster repeat use. Consistent practice with the same workflow usually leads to better accuracy, faster execution, and fewer avoidable mistakes.

This tool works entirely in your browser and does not require any downloads, plugins, or account registration. It is compatible with all modern browsers on desktop, tablet, and mobile devices. Because processing happens locally on your device, your data stays private and is never uploaded to external servers. Whether you are using Chrome, Firefox, Safari, or Edge, the experience is consistent and responsive across platforms.

Pregnancy Due Date Calculator is designed for a wide range of users, from students and freelancers to developers and marketing professionals. If your work involves health tools tasks, having a dependable browser-based utility eliminates the need to switch between multiple applications. For teams and collaborators, results can be copied, exported, or shared instantly without compatibility concerns. Explore our other health tools tools listed below to build a complete workflow that fits your needs.

How to use & Tips

Steps

1Enter the first day of your last menstrual period
2Enter your average cycle length (default is 28 days)
3View your estimated due date and current gestational age
4See key pregnancy milestones and trimester dates

Use Cases

-Calculate your baby's estimated due date
-Track current gestational age in weeks and days
-Identify which trimester you're in
-Plan prenatal appointments and milestones
-Share due date information with family

About Pregnancy Due Date Calculator

Everything you need to know about this tool and how to get the most out of it.

What is Pregnancy Due Date Calculator?

A pregnancy due date calculator estimates your expected delivery date (EDD) based on the first day of your last menstrual period (LMP). It also shows your current gestational age, trimester, and key pregnancy milestones.

How Pregnancy Due Date Calculator Works

Enter the first day of your last menstrual period and your average cycle length. The calculator uses Naegele's rule — adding 280 days (40 weeks) to your LMP — adjusted for your cycle length. It then calculates your current gestational age and upcoming milestones.

Why Use Pregnancy Due Date Calculator?

Knowing your due date helps you plan prenatal care, prepare for birth, and track your baby's development week by week. The trimester breakdown helps you understand what to expect at each stage of pregnancy.

Tips & Best Practices

1Only about 5% of babies are born on their exact due date — most arrive within 2 weeks before or after
2Your doctor may adjust your due date based on ultrasound measurements
3The first trimester ends at 13 weeks, the second at 27 weeks, and the third continues to 40+ weeks