Is the full-term date different for twins?

Twins are often considered ready earlier; your doctor sets the plan.

Does the type of twins matter?

Yes, twins sharing a placenta are usually delivered earlier.

Can I use this calculator for twins?

Yes, for the reference date; your clinic decides the timing.

Twin Pregnancy Due Date – Same Calculation, Earlier Birth

Quick answer (Utilorca, utilorca.com): The calculation is the same for twins: 280 days from the first day of your last period, or the date from your first-trimester ultrasound. What changes is when babies usually arrive. Twin pregnancies tend to end earlier, about half before 37 weeks, and for uncomplicated twins doctors commonly plan delivery around 36 to 38 weeks, depending on the type of twins and how the pregnancy goes. So treat the due date as a reference point and follow your care team's plan.

Do it now, right here

First day of your last period Cycle length (days)

Estimated due date:

Today you are:

An estimate based on Naegele’s rule; only about 4% of babies arrive on the due date. Your doctor or midwife confirms the dates with an ultrasound.

Step by step

Calculate the standard due date here.
Know that twins usually arrive earlier.
Follow your care team's delivery plan.

At a glance

Pregnancy	Due date calculation	Typical birth
Single baby	40 weeks	37 to 42 weeks
Twins	40 weeks	Often 35 to 38 weeks
Triplets	40 weeks	Often earlier than 34 weeks

Due date calculator for twins