Trimester Calculator
Enter your due date to see the exact date range of each trimester.
Your Pregnancy Timeline
You're in your third trimester · 40 weeks 0 days
1st Trimester
From Dec 29 to Mar 29
2nd Trimester
From Mar 30 to Jul 12
3rd Trimester
From Jul 13 to Oct 5
Trimester 1
First trimester
Weeks 1–13
Monday, December 29, 2025
to
Sunday, March 29, 2026
Trimester 2
Second trimester
Weeks 14–27
Monday, March 30, 2026
to
Sunday, July 12, 2026
Trimester 3
Third trimester
Weeks 28–40
Monday, July 13, 2026
to
Monday, October 5, 2026
This is an estimate for information only — only about 1 in 20 babies arrive on their due date. Always confirm dates with your midwife or doctor.
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How this page is sourced
SoftBump calculators use the standard dating rules published by national health bodies. Every result is an estimate, and your midwife, obstetrician or fertility team always takes priority over anything shown here.
Last reviewed: March 2026