Health & Fitness

Evidence-based formulas for body and training metrics.

Browse 27 free health & fitness tools that run entirely in your browser. No signup, no uploads, and no data stored — everything calculates or processes locally on your device. Use these tools for quick calculations, conversions, and everyday tasks with clear explanations and FAQs on every page.

BMI Calculator

Body mass index, WHO category, and your healthy weight range.

BMR Calculator

Calories your body burns at complete rest (Mifflin-St Jeor).

TDEE Calculator

Total daily energy expenditure: BMR scaled by real activity.

Calorie Calculator

Daily calories to maintain, lose, or gain weight at a healthy pace.

Macro Calculator

Grams of protein, carbs, and fat from your calorie target and split.

One Rep Max Calculator

Estimate your 1RM from any set, with training percentages.

Running Pace Calculator

Pace per km or mile from your distance and finish time.

Ideal Weight Calculator

Ideal body weight by three clinical formulas, shown as a range.

Body Fat Calculator

Estimate body fat percentage with the US Navy tape method.

Pregnancy Due Date Calculator

Your estimated due date and current pregnancy week from your last period.

Ovulation Calculator

Estimate your fertile window and ovulation day.

Sleep Calculator

Best bedtimes or wake times based on 90-minute sleep cycles.

Blood Alcohol (BAC) Calculator

A rough blood alcohol estimate from drinks, weight, and time.

A1C Calculator

Convert between A1C and estimated average glucose.

Heart Rate Zone Calculator

Your five training heart-rate zones from age and resting rate.

Water Intake Calculator

A daily hydration target from your weight and activity.

Protein Intake Calculator

Daily protein grams matched to your weight and goal.

Body Surface Area (BSA) Calculator

Body surface area by the Mosteller and Du Bois formulas.

Waist-to-Hip Ratio Calculator

Your waist-to-hip ratio and its health-risk category.

Smoking Cost Calculator

See what smoking costs per day, month, year, and decade.

Sleep Calculator

Best bedtimes and wake times based on 90-minute sleep cycles.

Water Intake Calculator

Daily water recommendation based on weight and activity.

Heart Rate Zone Calculator

Training heart rate zones from your age and resting HR.

Protein Intake Calculator

Daily protein recommendation based on weight and goal.

Calorie Deficit Calculator

How many calories to cut for a target weekly weight loss.

Waist-to-Height Ratio Calculator

Waist-to-height ratio as a simple health risk indicator.

Pregnancy Week Calculator

Current pregnancy week and trimester from last period.

Explore related categories