Which box is first day of last period
A practical, plain-English look at due-date estimate, the input mistakes to avoid and why the answer stays a rough estimate.
Read article →Simple numbers, clearly explained
Everyday health estimates without the long lecture.
Due date, water, calories, sleep, BMI — type the numbers, get a rough answer. Free calculators that work right in your browser.
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Due Date Calculator
Add 280 days to the first day of your last period.
Open calculator →Pregnancy Week Calculator
See estimated pregnancy weeks and days from LMP.
Open calculator →Water Intake Calculator
Estimate a daily water range from body weight.
Open calculator →BMI Calculator
Calculate BMI with metric or feet and inches.
Open calculator →Daily Calorie Estimate
Estimate maintenance calories with Mifflin-St Jeor.
Open calculator →Sleep Cycle Calculator
Count back 90-minute cycles from wake time.
Open calculator →Hours Slept Calculator
Measure time between sleep and wake times.
Open calculator →Steps to Kilometres
Convert steps to distance with adjustable stride.
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Three simple groups
Pregnancy dates
Rough date and week estimates to discuss at appointments.
Daily body
BMI, water, age, steps and tape-measure numbers.
Sleep food
Calories, protein and practical sleep-time maths.
From the desk
See all 40 articles →Latest practical articles
Screenshot result for the clinic bag
A practical, plain-English look at pregnancy-week estimate, the input mistakes to avoid and why the answer stays a rough estimate.
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Wake time 5 am too little cycles
A practical, plain-English look at sleep-cycle bedtime list, the input mistakes to avoid and why the answer stays a rough estimate.
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I typed height in feet in the cm box
A practical, plain-English look at BMI number, the input mistakes to avoid and why the answer stays a rough estimate.
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Do not use due date to skip a doctor
A practical, plain-English look at due-date estimate, the input mistakes to avoid and why the answer stays a rough estimate.
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Navy body fat I measured wrong
A practical, plain-English look at Navy-method body-fat estimate, the input mistakes to avoid and why the answer stays a rough estimate.
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Steps on phone and this tool differ
A practical, plain-English look at steps-to-distance estimate, the input mistakes to avoid and why the answer stays a rough estimate.
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Gym protein 1.6 vs 0.8
A practical, plain-English look at daily protein estimate, the input mistakes to avoid and why the answer stays a rough estimate.
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