Due Date Calculator

Congratulations! (Or surprise!). Whether you're planning a nursery or just curious, our Due Date Calculator uses the "Naegele's Rule" to predict when your little bundle of joy will arrive.

What this calculator does

• EDD: Estimated Due Date.
• Trimesters: When do you hit the "Safe Zone" (2nd)?
• Conception Date: Work backwards to see when it happened.

The Formula

$\text{Due Date} = \text{LMP} + 280 \text{ Days}$

• LMP: First day of Last Menstrual Period.
• Cycle: Assumes 28 days.
• Math: LMP + 7 Days - 3 Months + 1 Year.

Unlike math class, here's what that means

Pregnancy is technically 40 weeks, but you aren't actually pregnant for the first 2 weeks (before ovulation). So "Week 1" of pregnancy is actually your period. (Confusing, we know).

Example Calculation

LMP: Jan 1st.

1. Add 7 Days: Jan 8th.
2. Subtract 3 Months: Oct 8th.
3. Add 1 Year: October 8th. (Due Date).

Did You Know? 💡

• Only 4%: Only 4% of babies are born on their exact due date. It's an estimate window, not a deadline.
• Full Term: Anything from 37 weeks to 42 weeks is "normal."
• Hair & Heartburn: Old wives say heartburn means a hairy baby. A John Hopkins study actually found a correlation! (Progesterone relaxes the esophagus and also boosts hair growth).

Expert Insight

The "4th Trimester": The first 3 months after birth are crucial. The baby is technically still a fetus (useless outside the womb) and needs constant holding. Don't plan to "bounce back" instantly.

Why this matters

Knowing your due date helps you book scans, schedule work leave, and mentally prepare for sleepless nights.

Frequently Asked Questions

What if I don't know my LMP? Doctors use an early Ultrasound to measure the "Crown Rump Length" (CRL) of the baby. It's the most accurate way to date a pregnancy.

Can I choose my due date? No. But a C-section or induction can be scheduled around 39 weeks.

Is 42 weeks safe? Doctors usually induce labor by 41-42 weeks because the placenta starts to degrade and risks increase.

Related Calculators

• Ovulation Calculator: How it started.
• Pet Age Calculator: Practice with a puppy first?

Disclaimer: Every baby runs on their own schedule.