All Health & Fitness Calculators Tools
5-4-3-2-1 Grounding Exercise
Interactive guided grounding technique to calm anxiety and panic using your five senses
Barbell Plate Calculator
See exactly which weight plates to load on each side of the bar with a visual barbell diagram and warm-up sets
BMI Calculator
Calculate your Body Mass Index instantly, see your BMI category, healthy weight range, and track changes over time
BMR Calculator
Calculate your Basal Metabolic Rate using Mifflin-St Jeor, Harris-Benedict, and Katch-McArdle formulas with activity-level calorie estimates
Body Fat Percentage Calculator
Estimate your body fat percentage using the US Navy method with just a tape measure — no calipers or special equipment needed
Body Proportions Calculator
Calculate your body proportion ratios for fitness, fashion, and art. Compare against classical Greek ideals and gender-specific benchmarks instantly.
Body Recomposition Calculator
Calculate training day vs rest day calories and macros for building muscle while losing fat
Box Breathing Timer
Guided breathing exercises to reduce stress and improve focus — no signup required
Burnout Score Calculator
10-question burnout assessment with personalized recommendations — 100% private
Caffeine Intake Calculator
Track your daily caffeine intake from coffee, tea, energy drinks, and more. Compare to the FDA safe limit of 400mg per day.
Calorie Deficit Calculator
Calculate your daily calorie target and timeline to reach your goal weight based on TDEE and chosen rate of loss
Condom Size Calculator
Find the right condom size based on your measurements for proper fit, comfort, and safety
Contraction Timer
Time your contractions, track duration and intervals, and know when to head to the hospital with the 5-1-1 rule
Creatine Dosage Calculator
Calculate your optimal creatine monohydrate dosage for loading and maintenance phases based on body weight
Daily Habit Tracker
Track your daily habits with a visual 30-day grid, streak counter, and completion stats — all saved locally, no account needed
Digital Detox Calculator
See what you could accomplish with the time you spend on screens
Fitzpatrick Skin Type Quiz
Answer 6 questions to discover your skin type, sun sensitivity, and recommended SPF
Heart Rate Zone Calculator
Calculate your 5 heart rate training zones using the Karvonen formula for smarter cardio training
Ideal Weight Calculator
Calculate your ideal body weight using Devine, Robinson, Miller, and Hamwi formulas with BMI-based healthy range comparison
Intermittent Fasting Window Calculator
Plan your eating and fasting windows with a visual 24-hour clock for any IF protocol
Lean Body Mass Calculator
Calculate your lean body mass using Boer, James, and Hume formulas with body fat percentage estimate and visual breakdown
Macro Calculator
Calculate your daily protein, carbs, and fat targets based on your body stats, activity level, and diet goal
Meat vs Plant Diet CO₂ Comparison
Compare the carbon footprint of meat-based and plant-based diets and see how much CO₂ you could save
One Rep Max Calculator
Estimate your one-rep max from weight and reps using five proven strength formulas, plus get a full percentage chart
Ovulation Calculator
Predict ovulation dates, fertile windows, and best days to conceive for the next 6 cycles — free, private, no signup
Period Calculator
Predict upcoming periods, fertile windows, and ovulation days based on your cycle length — free, private, no signup
Pregnancy Week Calculator
Calculate your due date, current week, trimester, and baby milestones — free, instant, no signup
Pregnancy Weight Gain Calculator
Track recommended weight gain by week based on your pre-pregnancy BMI using IOM guidelines — free, instant, no signup
Protein Intake Calculator
Find your recommended daily protein intake based on body weight, activity level, and fitness goal
Running Pace Calculator
Calculate pace, finish time, or distance for any run — with splits table and race predictor
Safe Sun Exposure Calculator
Calculate safe sun time based on your skin type and UV index, with vitamin D production estimates and sunburn risk
Sleep Cycle Calculator
Calculate optimal bedtimes and wake-up times based on 90-minute sleep cycles for better, more restful sleep
Strength Standards Calculator
See how your squat, bench press, deadlift, and overhead press compare to population standards from beginner to elite
TDEE Calculator
Calculate your Total Daily Energy Expenditure, BMR, and macros for weight loss, maintenance, or muscle gain
Vitamin D Dosage Calculator
Get a personalized daily vitamin D supplement recommendation based on your current level, weight, age, and risk factors per Endocrine Society guidelines.
VO2 Max Calculator
Estimate your VO2 max from the Cooper Test, 1.5-mile run, Rockport Walk Test, or a recent race result
Waist-to-Hip Ratio Calculator
Calculate your waist-to-hip ratio instantly, see your health risk category based on WHO guidelines, and understand your body shape
Water Intake Calculator
Calculate your ideal daily water intake based on weight, activity level, climate, and caffeine consumption
Wilks & DOTS Score Calculator
Compare powerlifting strength across different bodyweights using Wilks and DOTS formulas
Work-Life Balance Wheel
Rate 8 life areas, visualize your balance as a radar chart, and get actionable insights
Health & Fitness Calculators on FastTools are free, browser-based tools designed to help you get quick answers without signups or downloads. Every calculator runs entirely in your browser — your data never leaves your device.
Whether you're planning, budgeting, or just curious, these tools are built to be fast, accurate, and private. Pick any tool below to get started instantly.
Frequently Asked Questions
Are these health & fitness calculators free?
Yes, every tool is completely free to use with no signup, no account, and no hidden fees.
Is my data safe?
Absolutely. All calculations run locally in your browser. No data is sent to any server or stored anywhere.
Do I need to create an account?
No. Every tool works instantly with no registration required. Just open and start using.