Pregnancy Calculator
Find how many weeks pregnant you are, your trimester, due date and key milestones from your last period — free online. — free, fast and private.
How to use Pregnancy Calculator
- Choose the first day of your last menstrual period.
- Click Calculate Pregnancy Week to see your week, trimester and due date.
- Confirm the result with your doctor or midwife.
Note: this tool runs in your browser. Nothing is uploaded.
Disclaimer: this is an estimator only — please see a qualified professional for advice about your specific situation. This is an estimate based on a regular cycle. Only a doctor or midwife, usually with an ultrasound, can confirm how far along you are. See a healthcare professional for prenatal care.
Frequently Asked Questions
How many weeks pregnant am I?
Count the weeks from the first day of your last menstrual period — that is how doctors date a pregnancy, even though conception happens about two weeks later. Enter your last period date above to get your current week and trimester.
Is this tool free to use?
Yes, it is 100% free with no sign-up. Your data stays in your browser.
Is my data uploaded or stored?
No. This tool runs entirely in your browser — nothing you enter is uploaded to a server.
Can I use it on my phone?
Yes, it is fully mobile-friendly and works in any modern browser on phone, tablet or computer.