Pregnancy Weeks Calculator

How to use Pregnancy Weeks Calculator

1. Open Pregnancy Weeks Calculator in your browser — it loads instantly and works offline once cached.
2. Enter your values in the input fields. Every field is labelled so you know exactly what to type.
3. The result updates automatically as you type — there is no "submit" round-trip to a server.
4. Adjust any input to compare scenarios and see how the outcome changes in real time.
5. Copy or note the result. Nothing you enter is stored or sent anywhere.

Why use Pregnancy Weeks Calculator?

• 100% free with no limits, no sign-up and no watermarks.
• Private by design — your data are processed in your browser and never uploaded to a server.
• Fast and lightweight, with instant results even on a phone or a slow connection.
• Works everywhere — any modern browser on Windows, macOS, Linux, Android or iOS.
• Part of a full date & time suite, so related pregnancy weeks tasks are one click away.

What people use Pregnancy Weeks Calculator for

• Converting a due date into current gestational weeks and days.
• Checking which trimester a given date falls in.
• Tracking progress against appointment schedules.

Pregnancy Weeks Calculator: limits and things worth knowing

• Gestational age is counted from the first day of the last menstrual period, not from conception, so it runs about two weeks ahead of embryonic age.
• Trimesters are conventionally weeks 1-13, 14-27 and 28-birth, though the exact boundaries differ slightly between sources.
• Weeks are usually expressed as weeks plus days — '24+3' means 24 weeks and 3 days — which is the notation used in maternity records.
• General information only; clinical dating from your care provider takes precedence.

Is it private and secure?

Your privacy is built in. Pregnancy Weeks Calculator runs completely on your device, so whatever you enter stays in your browser and is never transmitted, logged or stored on any server.

Network activity: none. Nothing is sent and nothing is fetched. This tool makes no network request at all once the page has loaded — which is why it keeps working if your connection drops.

You do not have to take that on trust — our privacy proof page publishes the Content-Security-Policy that enforces it, lists every third party it permits, and shows how to verify the whole claim yourself.

Learn more

Why Browser-Based Tools Are Safer for Your Files — Most online converters upload your files to a server. Client-side tools don't. Here's why that difference matters for privacy.