Health

Pregnancy Weeks Calculator

Find pregnancy progress from days since last period.

Calculated Output

Weeks 14

Plus days 2

Trimester Second

Days to due date 180

Formula: weeks = days ÷ 7 ; due at 280 days

Step-by-Step Breakdown

1. Values used:

2. Days since last period (LMP) = 100 days

4. Weeks = 14

5. Plus days = 2

6. Trimester = Second

7. Days to due date = 180

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The math behind it

Gestational age is counted from the LMP; weeks = days ÷ 7. Due date is ~280 days (40 weeks) from the LMP.

100 days → 14 weeks 2 days (2nd trimester).

Accurate?

An estimate — ultrasound dating is more precise.