Calculate due date
Get a clear estimated due date from your last period.
Due Date Calculator
Estimate your baby’s due date using your last menstrual period, conception date, or IVF transfer date.
Default is 28 days if unsure.
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Estimated Due Date
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Pregnancy Week
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Pregnancy Day
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Trimester
How the Due Date Calculator Works
The tool estimates your baby’s arrival date using Naegele’s Rule, adjusted for cycle length, or by counting forward a fixed number of days from a known conception or embryo transfer date.
LMP method: EDD = LMP + 280 days (adjusted for cycle length ≠ 28) Conception method: EDD = Conception date + 266 days IVF Day-5 transfer: EDD = Transfer date + 261 days IVF Day-3 transfer: EDD = Transfer date + 263 days
Benefits
- Plan prenatal visits and screening windows around your estimated timeline.
- Understand which trimester and developmental stage your baby is in today.
- Compare LMP-based and conception-based estimates for cross-checking.
Frequently Asked Questions
No. It is a statistical estimate. Only a small share of babies are born on their exact estimated due date; a range of two weeks before or after is considered normal.
Ovulation timing shifts with cycle length, so a longer or shorter cycle moves the estimated conception date and therefore the due date.
Because the exact embryo age is known at transfer, IVF-based estimates are generally considered more precise than LMP-based estimates.
This calculator is for general informational purposes only and does not replace medical advice, diagnosis, or treatment from a licensed healthcare provider. Always confirm your due date with your OB-GYN or midwife.
Pregnancy Week Calculator
Find out exactly how many weeks and days pregnant you are, and how many weeks remain.
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Weeks Pregnant
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Extra Days
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Weeks Remaining
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Trimester
How Pregnancy Weeks Are Counted
Pregnancy is measured in weeks from the first day of the last menstrual period, not from the day of conception, which typically occurs about two weeks later.
Weeks Pregnant = floor((Today − LMP) / 7) Extra Days = (Today − LMP) mod 7 Weeks Remaining = 40 − Weeks Pregnant
Benefits
- Track progress toward full term week by week.
- Know exactly which trimester you are currently in.
- Plan for appointments, screenings, and leave dates.
FAQs
Because pregnancy dating starts from the LMP, roughly two weeks before ovulation and conception even occur, so you are already several weeks along by the time of a missed period.
Full term is generally considered 39 to 40 weeks 6 days, with “early term” at 37-38 weeks and “post-term” after 42 weeks.
This tool provides estimates only. Consult your healthcare provider for a clinically confirmed gestational age, especially if dating by ultrasound differs from LMP dating.
Ovulation Calculator
Estimate your most fertile days and predicted ovulation date based on your cycle.
Default 14 days if unknown.
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Predicted Ovulation Day
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Fertile Window
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Next Expected Period
How Ovulation Is Estimated
Ovulation typically occurs a fixed number of days — the luteal phase — before the next period, counting backward from the end of the cycle rather than forward from its start.
Ovulation Day = LMP + (Cycle Length − Luteal Phase Length) Fertile Window = Ovulation Day − 5 through Ovulation Day + 1 Next Period = LMP + Cycle Length
Benefits
- Identify the days with the highest chance of conception.
- Support custom, non-28-day cycles for more personalized accuracy.
- Anticipate your next expected period.
FAQs
Sperm can survive in the reproductive tract for up to five days, while the egg survives about 24 hours after ovulation, creating a roughly six-day fertile window.
Yes, irregular cycles make calendar-based prediction less reliable; ovulation predictor kits or basal body temperature tracking can improve accuracy.
This calculator offers a statistical estimate, not a guarantee. It is not a form of contraception and should not be relied upon to prevent pregnancy.
Conception Date Calculator
Estimate when conception most likely occurred, based on your due date or last menstrual period.
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Estimated Conception Date
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Likely Range
How Conception Date Is Estimated
Conception generally occurs around the time of ovulation. Working backward 266 days from a due date, or forward from the last period using cycle length, produces a close estimate.
From Due Date: Conception ≈ Due Date − 266 days From LMP: Conception ≈ LMP + (Cycle Length − 14 days)
Benefits
- Useful for estimating a baby’s approximate age at events like family milestones.
- Cross-check paternity or timing-related questions with a clinician.
FAQs
No. This is a statistical estimate only and should never be used as evidence in legal or paternity matters; those require clinical or genetic testing.
Conception date estimates carry a margin of error of several days. Speak with a healthcare provider for clinically dated pregnancies via early ultrasound.
Pregnancy Weight Gain Calculator
Compare your current weight gain against the medically recommended range for your body type.
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Pre-Pregnancy BMI
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BMI Category
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Weight Gained So Far
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Recommended Total Range
How Recommended Weight Gain Is Determined
Guidelines from major obstetric bodies base total recommended weight gain on pre-pregnancy BMI category, since starting weight affects how much additional gain is healthy.
Underweight (BMI < 18.5): 28-40 lbs (12.7-18.1 kg) Normal (18.5-24.9): 25-35 lbs (11.3-15.9 kg) Overweight (25-29.9): 15-25 lbs (6.8-11.3 kg) Obese (30+): 11-20 lbs (5-9.1 kg) Twin pregnancies generally require 37-54 lbs (normal BMI)
Benefits
- Stay within a healthy, evidence-informed weight range.
- Spot rapid or insufficient gain early to discuss with your provider.
FAQs
Insufficient weight gain has been associated with lower birth weight, so it is worth discussing consistently low gain with your healthcare provider.
Yes, carrying twins generally calls for a higher total weight gain range than a singleton pregnancy at the same starting BMI.
Weight gain needs vary by individual health history. This tool is educational and does not replace guidance from your obstetric care provider.
Pregnancy BMI Calculator
Calculate your pre-pregnancy or current body mass index and see your category.
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BMI
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Category
BMI Formula & Categories
BMI = Weight (kg) / (Height (m))² Underweight: < 18.5 | Normal: 18.5-24.9 Overweight: 25-29.9 | Obese: 30+
Benefits
- Pre-pregnancy BMI is the starting point for personalized weight-gain guidelines.
FAQs
Weight-gain guidelines are based on pre-pregnancy BMI; use your weight from just before conception whenever possible for the most relevant category.
BMI is a screening tool, not a diagnostic measure, and does not account for muscle mass, frame size, or ethnicity-specific risk differences. Discuss results with your provider.
Baby Growth Calculator
See your baby’s estimated size, weight, and developmental milestones for any week of pregnancy.
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About the Size Of
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Length
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Weight
How Baby Growth Estimates Work
Estimates reflect population averages recorded in growth studies. Individual babies vary, and estimates near term rely on estimated fetal weight formulas from ultrasound measurements.
Benefits
- Visualize your baby’s growth trajectory across pregnancy.
- Understand what milestone is unfolding at your current week.
FAQs
Everyday object comparisons make abstract measurements like centimeters and grams easier to visualize week to week.
Growth figures are population averages for reference only. Your provider’s ultrasound measurements are the accurate source for your baby’s individual growth.
Pregnancy Nutrition Calculator
Estimate your recommended daily calorie intake based on trimester and activity level.
Values are converted before calculation.
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Baseline Calories
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Pregnancy Adjustment
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Total Daily Calories
Baseline is your estimated daily need before the pregnancy adjustment.
How Calorie Needs Are Calculated
Baseline needs are estimated with the Mifflin-St Jeor formula for women. Metric or imperial inputs are converted to centimeters and kilograms, scaled by activity level, then adjusted for pregnancy by trimester.
BMR = (10 × weight kg) + (6.25 × height cm) − (5 × age) − 161 Baseline = BMR × Activity Factor Trimester 1: +0 kcal | Trimester 2: +340 kcal | Trimester 3: +450 kcal
Benefits
- Avoid the myth of “eating for two” with realistic calorie targets.
- Adjust nutrition needs as pregnancy progresses.
FAQs
Most guidelines suggest no additional calories are needed in the first trimester beyond a woman’s usual intake.
This is a general estimate, not individualized medical nutrition therapy. Consult a registered dietitian or your provider, especially with gestational diabetes or multiples.
Postpartum Weight Loss Calculator
Generate a safe, gradual weight-loss timeline after delivery.
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Weight to Lose
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Safe Weekly Rate
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Estimated Duration
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Estimated Target Date
How the Timeline Is Built
Postpartum weight loss is generally considered safe at a gradual pace once the body has had initial time to recover, especially for breastfeeding parents whose caloric needs remain elevated.
Safe rate: 0.5-1 kg (1-2 lbs) per week, starting after week 6 postpartum Estimated Weeks = Weight to Lose / Weekly Rate
Benefits
- Set realistic, health-first expectations instead of crash-diet timelines.
- Accounts for breastfeeding energy needs.
FAQs
Gradual, moderate calorie reduction is generally considered compatible with breastfeeding, but very low-calorie diets are typically discouraged as they may affect milk supply.
Postpartum recovery varies widely. Get clearance from your healthcare provider before starting any weight-loss or exercise program after delivery.
Pregnancy Timeline Tracker: Week 1 to Week 40
Browse baby size, weight, and key milestones for every week of pregnancy.
| Week | Size Comparison | Length | Weight | Milestone |
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About the Timeline
This week-by-week tracker summarizes typical fetal development milestones from the first week of pregnancy dating through full term at week 40.
FAQs
Pregnancy dating conventionally starts from the last menstrual period, so weeks 1-2 occur before ovulation and conception actually take place.
Milestones represent typical development ranges and are for educational purposes only. Individual development can vary; consult your healthcare provider with any concerns.
