These calculators support fertility tracking and pregnancy planning — from the Ovulation Calculator and Conception Date Calculator to the Due Date Calculator and Pregnancy Weight Gain Calculator. The Menstrual Period Calculator helps you track your cycle over time, and the collection also includes gestation tools for animals, such as the Rabbit Gestation Calculator and Llama Gestation Calculator, useful for breeders and curious owners alike.
Browse the most-popular list to see which tools visitors reach for most, or open the Trending tab to find what's gaining attention right now. All calculators are free, need no sign-up, and work on any phone, tablet, or desktop.
- Body Composition Calculator
- Metabolism Calculator
- Nutrition Calculator
- Heart Health Calculator
- Pregnancy Calculator
- Fitness Calculator
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Pregnancy Weight Gain Tracker vs. RecommendedCompare your actual pregnancy weight gain to IOM-recommended targets by week and pre-pregnancy BMI. See if you are on track, above, or below.
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Pregnancy Weeks to Months CalculatorConvert weeks pregnant to months instantly. Enter your gestational age in weeks to see how many months pregnant you are, using 4.34524 weeks per month.
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Baby Weight-for-Age Percentile CalculatorFind your baby's weight-for-age percentile (0–24 months) using WHO growth standards. Enter sex, age, and weight to get z-score and percentile.
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Pregnancy Caffeine Limit CalculatorAdd up coffee, tea, soda, energy drinks and chocolate to see how much caffeine you've had and how much is left under the 200 mg/day pregnancy limit.
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Infant Length/Height-for-Age Percentile CalculatorEstimate your baby's length or height-for-age percentile (0-24 months) using WHO growth standards, a z-score and the normal distribution.
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Ovulation Date CalculatorEstimate your ovulation day and fertile window from the first day of your last period and your average cycle length. Free, fast, and easy to use.
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Naps Needed CalculatorEstimate how many naps per day are needed from total daytime sleep hours and average nap length. Free, instant nap schedule calculator for babies and adults.
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Gestational Age from LMP CalculatorCalculate gestational age in weeks and days from the last menstrual period (LMP). Enter the LMP date and today's date to get exact pregnancy weeks.
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Due Date from Ovulation/Conception CalculatorCalculate your estimated due date (EDD) from your ovulation or conception date by adding 266 days (38 weeks). Fast, free pregnancy date tool.
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Total Recommended Pregnancy Weight Gain CalculatorEstimate your recommended total pregnancy weight gain in kg from your pre-pregnancy BMI using the IOM 2009 guidelines for a single baby.
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Fertile Window CalculatorEstimate your most fertile days and ovulation date from your last period and cycle length. Find your 6-day fertile window to plan conception.
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How Many Weeks Pregnant Am I?Find out how many weeks and days pregnant you are from your last menstrual period (LMP). Enter your LMP and an as-of date to get gestational age instantly.
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Days Until Baby Is Born CalculatorCount down the days until your baby's due date. Enter the estimated due date and today's date to see days, weeks, and months remaining.
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Weeks Pregnant from Conception Date CalculatorFind out how many weeks pregnant you are based on the conception date. Calculates gestational age in weeks and days from conception to today.
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Baby Feeding Amount by Weight CalculatorEstimate how much formula or milk to feed your baby per day and per feed based on weight, using the standard 150 mL/kg/day guideline.
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How Many Months Pregnant Am I?Find out how many months pregnant you are. Enter your last menstrual period (LMP) and today's date to get gestational age in months, weeks and days.
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Baby Weight Conversion CalculatorConvert baby weight between pounds & ounces and grams/kilograms instantly. Free two-way birth weight converter using exact conversion factors.
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Ultrasound Due Date CalculatorConvert your ultrasound gestational age (weeks + days) into an estimated due date (EDD). Enter the scan date and GA to get your pregnancy due date instantly.
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Basal Body Temperature (BBT) Ovulation CalculatorFind your ovulation day and fertile window from basal body temperature. Enter your 6-day baseline and thermal shift day to detect ovulation.
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Gestational Age from Ultrasound CalculatorCalculate estimated due date (EDD) and current gestational age from an ultrasound scan date and the gestational age measured at that scan.
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Pregnancy Calorie Needs CalculatorEstimate daily calorie needs during pregnancy. Adds the recommended extra kcal per trimester (0/+340/+450) to your maintenance TDEE.
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Pregnancy Trimester End Dates CalculatorCalculate the start and end dates of each pregnancy trimester and your estimated due date from your last menstrual period (LMP) and cycle length.
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Fetal Movement Kick Count CalculatorTime how long it takes to feel 10 fetal movements. Calculates elapsed minutes, pace per kick, and flags if it exceeds the 2-hour guideline.
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Weeks Pregnant CalculatorFind out how many weeks pregnant you are today. Calculate gestational age in weeks and days from your last menstrual period (LMP) date.
Frequently asked questions
What can I calculate in this category?
You can estimate your due date, find likely conception dates, predict upcoming ovulation windows, track your menstrual cycle across months, and monitor healthy weight gain during pregnancy. The animal gestation tools calculate expected birth dates for rabbits, llamas, and other species based on their typical gestation periods.
How accurate are the due date and ovulation estimates?
Dates are calculated using standard obstetric methods — for example, Naegele's rule for due dates and average cycle-length models for ovulation windows. Results are estimates; actual dates vary between individuals. These tools are NOT medical advice — consult a qualified healthcare professional or midwife for guidance throughout your pregnancy.
Do the animal gestation calculators use real biological data?
Yes — each calculator is based on the documented average gestation length for that species (roughly 31 days for rabbits, approximately 350 days for llamas). They provide a practical planning aid for breeders and owners, but individual variation is always normal.
Do you store personal health information I enter?
No. All calculations run in your browser. Last menstrual period dates, cycle lengths, and other personal details are never sent to our servers or retained after you close the page.
Which pregnancy calculators are most popular?
The list is ranked by real visitor usage, reflecting which tools people find most useful. Switch to the Trending tab to see what's seeing the fastest growth right now, or Recently Added for the newest arrivals.
