All calculatorsAbout UsContact UsPrivacy PolicyTerms & Conditions

IVF Due Date Calculator

Enter your transfer date and embryo age to estimate your due date.

Estimated due date

—

Current gestation

—

What this calculator does

This calculator estimates an IVF pregnancy's due date using the standard clinical formula: 266 days minus the embryo's age in days at transfer, added to the transfer date. It also shows your current gestational age based on a standard 40-week pregnancy.

Worked example

A Day 5 blastocyst transferred on January 1, 2026 gives an estimated due date ofSeptember 19, 2026 (261 days later).

Common mistakes

  • Using the retrieval date instead of the transfer date. For a fresh transfer these are close together, but for a frozen embryo transfer (FET) they can be months apart — use the actual transfer date.
  • Applying the LMP formula from a standard pregnancy due date calculator (280 days) to a transfer date. That would overestimate the due date by about 2–3 weeks, since it doesn't account for the known embryo age.
  • Mixing up Day 3 and Day 5 embryo age. Using the wrong embryo age shifts the estimate by 2 days — check your clinic's transfer report for the exact day.

Frequently asked questions

Why is the IVF due date formula different from a regular pregnancy calculator?+

A regular due date estimate is based on the last menstrual period, which is roughly 2 weeks before ovulation/conception. With IVF, the embryo's exact age at transfer is known precisely, so the due date is calculated directly from the transfer date and embryo age instead of guessing backward from a period date.

What's the difference between a Day 3 and Day 5 transfer?+

A Day 3 transfer uses an embryo 3 days past fertilization (a cleavage-stage embryo); a Day 5 transfer uses a blastocyst-stage embryo. The due date formula adjusts for this so both methods point to the same estimated conception date.

How accurate is this due date?+

IVF due dates calculated this way are generally considered more precise than LMP-based estimates, since the fertilization date is exactly known. Your fertility clinic's own estimate, often confirmed by an early dating ultrasound, should be treated as authoritative.

Is this calculator medical advice?+

No — it's a planning estimate using the standard clinical formula. Always follow the due date and monitoring schedule provided by your fertility clinic or OB-GYN.

How do you calculate an IVF due date online from a transfer date?+

Subtract the embryo's age in days from 266, then add the result to the transfer date (266 − embryo age = days from transfer to due date). For a Day 5 transfer that's 261 days; for a Day 3 transfer it's 263 days.

Related calculators

Age CalculatorCalculate exact age in years, months, and days.Anniversary CalculatorFind your next anniversary and years together. Next Birthday CalculatorFind how many days until your next birthday.Days Alive CalculatorFind out how many days you've been alive.