Pregnancy Due Date Calculator

Estimate your baby's arrival date and track your pregnancy week by week.

About Pregnancy Due Date Calculator

This pregnancy due date calculator uses Naegele's rule, a standard method for estimating your baby's due date. Starting from the first day of your last menstrual period (LMP), it adds 280 days (40 weeks) and adjusts for your cycle length. Knowing your due date helps you plan prenatal care, track your baby's development by week, and prepare for the big day. Always consult your healthcare provider for personalized medical advice.

Naegele's Rule

Based on the classic 280-day gestational period, the standard method used by obstetricians and midwives worldwide.

Trimester Tracking

See which trimester you're in and get a clear view of your pregnancy progress from conception to due date.

Milestone Dates

View key pregnancy milestones including conception date, trimester start dates, and the estimated due date.

Cycle Adjustable

Customize your cycle length for a more accurate estimate — perfect for those with shorter or longer cycles.

📋 Common Use Cases

Track Your Health Progress

Monitor changes in your health metrics over weeks and months. Regular tracking helps you see trends, stay motivated, and adjust your fitness or nutrition plan based on real data.

Set Realistic Fitness Goals

Use your calculated metrics to set achievable weight, nutrition, and fitness targets. Understand your baseline numbers before starting any new diet or exercise program.

Professional Health Assessment

Healthcare professionals, personal trainers, and coaches can quickly compute client metrics during consultations without accessing specialized equipment or software.

Nutrition & Diet Planning

Use your results to plan meal portions, macronutrient targets, and daily calorie budgets. Combine multiple health calculators for a complete wellness picture.

🪜 How to Use This Tool

  1. Enter your body measurements
    Fill in the required fields — typically height, weight, age, and gender. Use the unit toggles if you prefer metric or imperial units.
  2. Add optional details if available
    Some calculators accept additional inputs like activity level, waist circumference, or body fat percentage for more precise results.
  3. Review your calculated metrics
    Your results appear instantly with clear labels and reference ranges. Color-coded indicators show where you fall on standard health classification scales.
  4. Track changes over time
    Bookmark the page and return periodically to recalculate. Comparing results over weeks and months reveals meaningful health trends.

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Frequently Asked Questions

Are these calculators really free?▼
Yes. All calculators on iluv.tools are completely free. No signup, no account, no credit card required. Every calculation runs instantly in your browser.
Is my data sent anywhere?▼
Absolutely not. All calculators are pure client-side JavaScript. Your numbers, dates, and inputs never leave your browser. No server processing, no tracking.
How accurate are these calculators?▼
Calculators use standard mathematical formulas with double-precision floating point. Results match industry-standard financial and scientific calculations.
Can I use calculators on mobile?▼
Yes. All calculators work on mobile browsers (iOS Safari, Android Chrome) with responsive layouts.