Health Calculators
Calculate BMI, calories, macros, heart rate zones, pregnancy dates, hydration, fitness metrics, body composition, and wellness estimates.
How to choose the right tool
Health calculators are best for estimates, tracking, and planning. Choose the tool that matches the measurement you already have or the goal you want to explore.
Most health tools support metric and imperial inputs. Results are educational estimates and should be interpreted with personal context.
Choose by need
- Use body measurement tools for BMI, body fat, waist-to-hip ratio, or ideal weight context.
- Use nutrition tools for calories, macros, protein, caffeine, hydration, and net carbs.
- Use fitness tools for pace, heart-rate zones, VO2 max, one-rep max, and training estimates.
Common tasks
- Estimate daily calories before setting a nutrition target.
- Convert steps to distance or pace to finish time.
- Check a broad body-composition or pregnancy-date estimate.
Choose a tool and get an instant result
BlinkCalc tools are designed to be fast, practical, privacy-conscious, and easy to understand. Many tools process inputs directly in your browser; tools that need a remote request explain that processing on their page.
BAC Calculator
Estimate your blood alcohol content based on drinks, weight, and time.
Bench Press Calculator
Estimate your bench press one-rep max from any weight and rep count.
Blood Pressure Calculator
See your blood pressure category from systolic and diastolic readings.
BMI Calculator
Calculate your body mass index and understand the result category.
BMI Prime Calculator
Calculate your BMI Prime ratio and understand your weight status.
BMR Calculator
Find your Basal Metabolic Rate and Total Daily Energy Expenditure.
Body Fat Calculator
Estimate your body fat percentage using the US Navy method.
Caffeine Calculator
Find out how much caffeine is safe per day and how long it stays in your system.
Calorie Burn Calculator
Estimate calories burned during exercise using MET values.
Calorie Calculator
Calculate your daily calorie needs (TDEE) and personalised macro split.
Due Date Calculator
Estimate your baby's due date and pregnancy milestones.
Heart Rate Zone Calculator
Calculate your five training heart rate zones based on your max heart rate.
Ideal Weight Calculator
Find your ideal body weight range using multiple established formulas.
Keto Calculator
Calculate your personalised keto macros for fat loss or maintenance.
Lean Body Mass Calculator
Calculate your lean body mass using the Boer, James, and Hume formulas.
Macro Calculator
Calculate your daily protein, carbs, and fat targets for your goal.
Net Carb Calculator
Calculate the net carbs in any food by subtracting fiber and sugar alcohols.
One Rep Max Calculator
Estimate your one-rep max for any lift using proven formulas.
Ovulation Calculator
Estimate your ovulation date and fertile window.
Peptide Calculator
Calculate peptide concentration, dose volume after reconstitution.
Period Calculator
Estimate your next period, fertile window, and ovulation date.
Pregnancy Calculator
Find out how many weeks pregnant you are and your trimester.
Protein Intake Calculator
Calculate your optimal daily protein intake based on your weight and activity level.
Pushup Calculator
Estimate your push-up fitness level using your age, sex, and maximum strict push-up count. Compare your results with broad fitness benchmarks and track progress over time.
Running Pace Calculator
Calculate your running pace, time, or distance for any race distance.
Sleep Calculator
Find the perfect bedtime or wake-up time based on 90-minute sleep cycles.
Steps to Miles Calculator
Convert your daily step count to miles or kilometers walked.
Swimming Pace Calculator
Calculate your swimming pace per 100m or 100 yards for any distance and time.
TDEE Calculator
Calculate maintenance calories, BMR, activity-adjusted TDEE, goal calories, and macro estimates.
VO2 Max Calculator
Estimate your VO2 max fitness level from a simple step test or running time.
Waist-to-Hip Ratio Calculator
Calculate your waist-to-hip ratio and understand your cardiovascular risk.
Water Intake Calculator
Calculate how much water you should drink per day.
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Frequently asked questions
Are these a substitute for medical advice?
No. Tools like BMI, calorie, and blood pressure calculators are educational and self-tracking aids. Always speak to a qualified healthcare professional before making decisions about your health.
Where do the formulas come from?
Each calculator uses widely accepted formulas (Mifflin-St Jeor for calories, US Navy method for body fat, standard BMI ranges, etc.) and each tool page explains the formula it uses.
Is my health data private?
Yes. All inputs stay in your browser. Nothing is uploaded, logged, or shared.