# Pregnancy due date calculator: weeks and trimester

> Find your due date, current week and trimester from your last period or conception date, with key milestones. Free pregnancy calculator online.

Home: https://funworks.app/en/ · HTML: https://funworks.app/en/calcie/pregnancy/

*An estimated due date and how far along you are, from the date of the last period or the date of conception.*

## What it calculates

Our pregnancy calculator online estimates the due date and the current stage in weeks and days from the first day of your last period (taking cycle length into account) or from the conception date. It shows the trimester and how many days are left.

The calculation uses Naegele's rule. It's a guideline, and your doctor will determine the exact stage with an ultrasound.

- Calculation from the first day of the last period, taking cycle length into account
- Calculation from the conception date
- Weeks and days along on any date, and the trimester
- How many days are left

## How to use it

1. Choose a method: “Last period” or “Conception”.
2. Enter the date and the cycle length if it isn't 28 days.
3. See the due date and how far along you are now.

## Example

First day of the last period and a 28-day cycle → **due date in 280 days**

## FAQ

**How accurate is it?**

It's an estimate based on Naegele's rule. Your doctor determines the exact due date with an ultrasound.

**Is a cycle longer than 28 days taken into account?**

Yes, enter a cycle length from 20 to 45 days and the date shifts accordingly.

**Why might the due date differ from the ultrasound?**

The calculation from your last period assumes ovulation in the middle of the cycle. If it happened earlier or later, the ultrasound dating will be more accurate, and your doctor may adjust the date.

**Does the “Pregnancy” mode work offline?**

Yes. Calcie does all its math right on your device, so the mode works on a plane, on the subway and out of town. Nothing is sent to any server, and the answer appears instantly.

**Is “Pregnancy” available on iPad and Mac?**

Yes. On iPad the mode has its own layout with larger fields, and on a Mac with Apple Silicon Calcie runs in its iPad version and works from the keyboard. Your Premium purchase applies on every device signed in with your Apple ID.

**How do I switch to the “Pregnancy” mode?**

Open the modes menu, the icon at the top left of the calculator's main screen, and choose “Pregnancy”. Calcie remembers your choice: next time the app opens right in that mode.

Try it right here: https://funworks.app/en/calcie/pregnancy/#calc · App Store: https://apps.apple.com/app/id6819202153

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FunWorks · https://funworks.app/en/ · support@funworks.app