Pregnancy Due Date Calculator
Calculate your estimated due date (EDD) from last menstrual period (LMP). Trimesters and key milestones.
How EDD is calculated
Your estimated due date (EDD) is your last menstrual period (LMP) plus 280 days (40 weeks). This is Naegele's rule. If your cycle is longer or shorter than the typical 28 days, the calculator adjusts: a 30-day cycle adds 2 days; a 26-day cycle subtracts 2.
Trimesters & milestones
- 1st trimester — weeks 1–12. First antenatal visit, NHIF maternity activation.
- 2nd trimester — weeks 13–26. Anomaly scan around week 20.
- 3rd trimester — weeks 27–40. Delivery prep, hospital choice, leave planning.
Tanzania practicalities
- Antenatal care is free at most public clinics; NHIF covers private/mission hospitals.
- NSSF maternity benefit pays 100% of salary for 84 days every 3 years if you have 36 contribution months.
- Maternity leave — 84 calendar days, paid by NSSF (employer tops up if NSSF rate is below salary).
- Public hospitals like Muhimbili, KCMC, Bugando, MOI — high-volume, low cost; private like Aga Khan, Regency, Premier Care — higher cost, faster service.
See the Leave Days Calculator for maternity-leave timing and the NHIF Calculator for cover.
Frequently asked questions
Is the Pregnancy Due Date Calculator free?
Are the figures up to date for 2026?
Can I use this on mobile?
Where do the formulas come from?
Want this automated for your business?
Tawala bundles every Tanzanian tax, payroll and compliance calculation — and files it for you. From TZS 75,000/month.
Email me a branded PDF of Pregnancy Due Date
Save the result. Share it with your accountant. Get one follow-up email with practical tips on automating this in your business — then we leave you alone unless you ask.
🔒 We store your email in Tanzania. Used only to send your PDF and occasional Tawala tips. You can unsubscribe in one click. We never sell or share your email.