Online Pregnancy Calculator

What Is This Tool?

The Pregnancy Calculator estimates how far along a pregnancy is, based on whichever date you have to work from. You can calculate from a due date, the first day of your last period, an ultrasound, a conception date, or an IVF transfer date, with adjustments for cycle length and embryo transfer age where relevant. It then reports the current pregnancy week and the gestational age in weeks and days as well as months and days. If the entered dates fall outside a viable range, it shows a "not currently pregnant" message instead. Dates use a native picker, and the result can be downloaded as a PDF.

How to Use This Tool?

• Choose what to calculate from in the dropdown.
• Enter the relevant date, plus any cycle length, gestational age, or embryo age it asks for.
• Click Calculate to see your current week and how far along you are.
• Download the result as a PDF if you'd like a copy.

Key Features

• Estimates how far along a pregnancy is from five different starting points.
• Accepts due date, last menstrual period, ultrasound, conception date, or IVF transfer date.
• Adjusts for cycle length (22–44 days) and embryo transfer age (day 3, 5, or 6).
• Reports the current pregnancy week plus gestational age in weeks/days and months/days.
• Uses native date pickers and offers a one-click PDF download.

Examples

• With a last period 56 days ago and a 28-day cycle, it shows week #9 — 8 weeks, 0 days.
• From a due date set 200 days out, it reports the current gestational age by counting back 40 weeks.
• An IVF Day 5 transfer 40 days ago returns roughly 8 weeks, 3 days.
• Dates that fall outside a viable range return a "not currently pregnant" message.

Common Use Cases

• Checking how many weeks along you are right now.
• Estimating gestational age from an early ultrasound.
• Translating an IVF transfer date into pregnancy progress.
• Confirming dating from a known conception date.
• Adjusting an estimate for a non-standard cycle length.

Tips & Best Practices

• Pick the input you have the most reliable date for.
• Enter your actual average cycle length rather than assuming 28 days.
• For ultrasound dating, use the gestational age the scan reported.
• Match the embryo age to your transfer (day 3, 5, or 6).
• Treat the result as an estimate and confirm dates with your provider.

Limitations

• Results are estimates based on a standard 40-week model and average cycle assumptions.
• It isn't medical advice and doesn't replace ultrasound dating or a provider's assessment.
• It reports current progress, not a guaranteed delivery date.
• Nothing is saved between sessions — only the current result can be exported as a PDF.

Frequently Asked Questions

What does this calculator tell me?

It estimates how far along you are now — your current pregnancy week and gestational age in weeks/days and months/days.

Which dates can I use?

Your due date, the first day of your last period, an ultrasound, a conception date, or an IVF transfer date.

Why does cycle length matter?

Cycles longer or shorter than 28 days shift ovulation, so the tool adjusts dating from your last period accordingly.

Why did it say "not currently pregnant"?

The entered dates produced a gestational age outside the viable range, such as below zero or beyond about 43 weeks.

Key Terminology

Gestational age

How far along a pregnancy is, usually counted from the first day of the last menstrual period.

Last menstrual period (LMP)

The first day of your most recent period, a common reference point for dating a pregnancy.

Due date

The estimated date of delivery, about 40 weeks after the last menstrual period.

Conception date

The day fertilization occurs, roughly two weeks after the last menstrual period.

Embryo transfer day

In IVF, the embryo's age at transfer (day 3, 5, or 6), used to back-date the pregnancy.

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