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Health & Wellness

How to Use the Due Date Calculator

Enter the first day of your last menstrual period, and the calculator estimates a due date roughly 280 days later, along with the current estimated week of pregnancy — this is a general estimate for informational purposes and should be confirmed and monitored by a healthcare provider.

The Due Date Calculator provides a general estimate based on standard assumptions — here's what to enter, and an important note on how to use the result.

Entering the last period date

Enter the first day of the most recent menstrual period — the calculator applies the standard 280-day estimation method to project an estimated due date and current gestational week.

Using the result appropriately

This tool provides a general, informational estimate only — it is not a substitute for medical care. Confirming and monitoring an actual due date and pregnancy progress should always be done with a qualified healthcare provider, who can incorporate clinical information this calculator doesn't have access to.

Frequently asked questions

Is this calculator a substitute for a doctor's estimate?

No — it's intended as a general informational estimate only. Always rely on a healthcare provider for actual pregnancy dating, monitoring, and care decisions.

What if I don't remember my exact last period date?

Enter your best estimate for a rough calculation, but discuss dating directly with a healthcare provider, who has other methods (like ultrasound) available when the last period date is uncertain.