Pregnancy Due Date Calculator
Enter the first day of your last period and cycle length, and get your estimated due date (Naegele's rule, cycle-adjusted), exactly how far along you are today, trimester boundaries and the dates for anomaly scan and NT scan. No account, no tracking, no data stored.
🔒 100% Private — runs in your browser, nothing is uploadedCómo usar This Pregnancy Due Date Calculator (Step-by-Step)
- Enter last period start — First day of your most recent period.
- Add cycle length — Default 28 days; adjust if yours differs.
- Read your timeline — Due date, today's week and scan dates appear.
Naegele's Rule, Modernized — Under the Hood
The classic formula (LMP + 7 days − 3 months + 1 year) assumes 28-day cycles with day-14 ovulation. For a 32-day cycle, ovulation lands around day 18, so the due date shifts +4 days — exactly what this calculator does: 280 days from LMP plus (cycle − 28).
Frequently Asked Questions
How accurate is the due date?
Only ~4% of babies arrive on the exact date; it is a reliable 2-week window.
Why adjust for cycle length?
Ovulation shifts with longer cycles — the tool adds the difference to the standard 280-day count.
Is my data saved?
Never. Everything computes in your browser and disappears on refresh.
Related Free Tools
Resumen rápido
Pregnancy Due Date Calculator — 100% Free, No Signup is a practical NexVaani tool for completing this task quickly in your browser. Calculate pregnancy due date from last period, current week, trimester and key scan milestones — private and instant. Use the tool, review the result, and continue with a related NexVaani tool when your workflow needs another step.