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Pregnancy Due Date
Calculate expected baby delivery date from last menstrual period.
2026 tax-year compliantSwitch to Japanese version
Pregnancy Due Date
Calculate expected baby delivery date from last menstrual period.
- 1. Enterfill in details
- 2. Calculateclick the button
- 3. Resultshown instantly
Key Points
- ✓Gestation: 280 days from LMP
- ✓Trimester 1: 0-13 weeks
- ✓Trimester 2: 14-26 weeks
- ✓Trimester 3: 27-40 weeks
FAQ
Same as international standard?
Yes — 280 days from last period (LMP). Naegele's rule.
⚠️ Disclaimer
This calculator provides estimates only. For actual tax filing, please consult a licensed 税理士 (zeirishi) or FP (Financial Planner). Results are not a substitute for professional advice.
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