FREE ONLINE TOOLS
❤️ Free Health Tools
Browse 31 free health tools on FastTool. All tools run in your browser with no signup required.
About Our Health Tools
Keeping track of health metrics is easier when you have the right calculators at your fingertips. FastTool's free health tools let you compute BMI, estimate calorie needs, track body fat percentage, convert medical units, and more. Every calculation runs locally in your browser, which means your personal health data is never sent to a server or stored anywhere. Whether you are a fitness enthusiast planning a diet, a student studying nutrition, or simply curious about your health numbers, these tools provide quick, reliable results based on standard medical formulas. They are not a substitute for professional medical advice but are perfect for day-to-day tracking.
All Health Tools (31)
BMI Calculator
Calculate BMI from weight and height, view category and healthy range.
Calorie Calculator
Calculate daily calorie needs based on age, weight, and activity level.
Breathing Exercise
Guided breathing timer with 4-7-8 and box breathing patterns.
Water Intake Calculator
Calculate your recommended daily water intake.
Sleep Calculator
Calculate optimal sleep and wake times based on sleep cycles.
Pregnancy Due Date Calculator
Estimate your due date, trimester, and weeks pregnant from your last period.
Heart Rate Zone Calculator
Calculate your heart rate training zones based on age and resting heart rate.
Macro Calculator
Calculate daily protein, carbs, and fat grams based on calorie intake and goal.
Body Fat Calculator
Estimate body fat percentage using the US Navy method.
Calories Burned Calculator
Estimate calories burned for common activities using MET values.
Pregnancy Calculator
Calculate your due date, weeks pregnant, trimester, and upcoming milestones from your LMP.
Ovulation Calculator
Calculate your ovulation window and fertile days based on your cycle length.
Blood Type Compatibility
Check blood type compatibility for transfusions and organ donations, and find your Rh factor details.
Pace Calculator
Calculate running or walking pace, finish time, or distance — essential tool for runners, cyclists, and fitness enthusiasts.
Ideal Weight Calculator
Calculate your ideal body weight based on height and gender using multiple medical formulas — Hamwi, Devine, Robinson, and Miller.
Waist-to-Hip Ratio Calculator
Calculate your waist-to-hip ratio and see your cardiovascular health risk level — supports cm and inches for both men and women.
Eye Care Timer (20-20-20)
Protect your eyes with the 20-20-20 rule — every 20 minutes, get reminded to look 20 feet away for 20 seconds. Includes desktop notifications.
Reaction Time Test
Measure your reaction time in milliseconds — wait for the green signal, click as fast as possible, and see your average across 5 rounds with a performance rating.
Calorie Deficit Calculator
Calculate the exact calorie deficit needed to hit your weight loss goal — enter your stats, choose your activity level, and get a personalized daily calorie target with a timeline.
TDEE Calculator
Calculate your Total Daily Energy Expenditure (TDEE) — enter age, weight, height, gender, and activity level to get daily calorie needs for maintenance, loss, and gain.
Menstrual Cycle Calculator
Track your menstrual cycle — enter your last period start date and average cycle length to predict your next period, fertile window, and ovulation day up to 6 months ahead.
Sleep Debt Calculator
Calculate your cumulative sleep debt — enter your actual vs ideal sleep for the past week and see how many hours behind you are, plus tips to recover your sleep deficit.
BAC Calculator
Estimate your Blood Alcohol Content (BAC) based on drinks consumed, body weight, gender, and time elapsed — know when it's safe to drive with a science-based formula.
Intermittent Fasting Timer
Track your intermittent fasting window with a real-time countdown. Choose from popular protocols (16:8, 18:6, 20:4, OMAD, 5:2) or set a custom schedule.
Heat Index Calculator
Calculate the apparent 'feels like' temperature by combining actual air temperature and relative humidity. Get heat risk level, safety guidelines, and understand how humidity amplifies heat stress on your body.
Blood Pressure Checker
Check if your blood pressure reading is normal, elevated, or in a hypertension stage. Enter your systolic and diastolic values and instantly see your BP category, risk level, and recommended actions based on AHA guidelines.
Keto Calculator
Calculate your ideal ketogenic diet macros — fat, protein, and carbohydrates — based on your body weight, height, age, activity level, and goal. Get daily calorie targets and macro percentages for entering and maintaining ketosis.
Sleep Cycle Calculator
Calculate the best times to wake up or go to sleep based on 90-minute sleep cycles. Enter your bedtime or desired wake time to find optimal sleep windows that help you wake up feeling refreshed instead of groggy.
Calorie Burn Calculator
Estimate calories burned during exercise based on activity type, body weight, and duration. Supports 30+ activities from running and cycling to yoga and swimming. Uses MET (Metabolic Equivalent of Task) values for accurate estimates.
Health Insurance Cost Comparison
Compare health insurance plan tiers and estimate your total annual healthcare costs.
HSA Contribution & Savings Calculator
Calculate HSA tax savings, projected balance, and investment growth through retirement.