🧮 Calculators

Pregnancy Due Date Calculator

Estimate your baby's due date, current pregnancy week, and trimester. Uses Naegele's rule with cycle length adjustment. See major pregnancy milestones.

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Calculation method

First day of last menstrual period

Cycle length (days)

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Your Pregnancy Timeline

Estimated Due Date

Weeks pregnant

Trimester

Days remaining

Conception (approx)

Pregnancy progress

Key Milestones

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ℹ️ This is an estimate for planning purposes only. Only about 5% of babies arrive on their exact due date. Most arrive within 2 weeks either side. Always consult your doctor or midwife for medical guidance.

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How it works

Pick Method

LMP is standard. Conception date if known (e.g., IVF).

Enter Date

First day of your last period, plus cycle length.

See Due Date

Get due date, weeks, trimester, and milestones.

Frequently asked questions

How accurate is a due date calculator?

Standard calculators use Naegele's rule (LMP + 280 days) which assumes a 28-day cycle and ovulation on day 14. We adjust for your actual cycle length. Only 4-5% of babies are born on their exact due date, but 80% arrive within 2 weeks either side.

LMP vs conception date - which should I use?

LMP is most common because most people know that date. Use conception date if you had IVF, tracked ovulation precisely, or your doctor gave you a specific date via ultrasound.

Why does cycle length matter?

Standard formula assumes ovulation on day 14 of a 28-day cycle. If your cycle is 30 days, you ovulate around day 16, so your due date shifts 2 days later. We adjust for this automatically.

Is my data uploaded?

No. All calculation happens in your browser. Your dates and personal info never leave your device.

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