Health & Fitness

Convert between HbA1c percentage and estimated average glucose (eAG) in mg/dL or mmol/L using the ADA formula.

Calculate how much formula to feed your baby based on age and weight using standard pediatric guidelines (150 ml/kg/day). Covers newborn to 12 months.

Estimate your blood alcohol content (BAC) using the Widmark formula. Enter drinks, weight, sex, and hours drinking for an instant BAC estimate.

Estimate your biological age based on lifestyle factors including BMI, blood pressure, exercise, sleep, diet, smoking status, and alcohol intake. See how your habits add or subtract years.

Enter your systolic and diastolic blood pressure to see your AHA/ACC category: Normal, Elevated, Stage 1 or Stage 2 Hypertension, or Hypertensive Crisis.

Calculate Body Mass Index in metric or imperial. WHO classification and healthy weight range.

Calculate your Basal Metabolic Rate and Total Daily Energy Expenditure using Mifflin-St Jeor or Harris-Benedict.

Calculate your body fat percentage using the US Navy circumference method. Supports metric and imperial, shows ACE classification and lean body mass. Free and private.

Determine your body frame size (small, medium, or large) using the wrist circumference method. See your frame-adjusted ideal weight range.

Guided breathing exercises with animated circle. Choose from box breathing, 4-7-8, resonance, and more. Reduce stress and improve focus.

Calculate how many calories you burn during exercise or daily activities. Enter your weight, activity type, and duration to get an instant estimate based on MET values.

Track your daily calorie intake with a simple food log. Set a daily calorie goal, add meals and snacks, and see how much you have left for the day.

Calculate your child's weight and height percentile based on WHO/CDC reference data for ages 0-18 years. See where your child falls compared to the reference population.

Calculate your 7 cycling training zones from your Functional Threshold Power (FTP). Enter your FTP or estimate it from a 20-minute test to get power ranges for each zone.

Calculate cycling power output (watts), speed, distance, or time using a physics-based model. Includes FTP power zones.

Calculate your personalized daily water intake based on body weight, activity level, and climate. Get recommendations in liters, cups, and ounces.

Calculate the Glycemic Load (GL) of any food using its Glycemic Index (GI), carbohydrate content, and fiber. Includes a reference table of common foods.

Track daily habits with a visual grid, streak counter, and localStorage persistence. Add habits, mark completions, and watch your streaks grow. No account required.

Calculate your 5 training heart rate zones (Z1–Z5) from your age and resting heart rate. Supports Classic, Tanaka, and Karvonen methods. Free and private.

Calculate the heat index (feels-like temperature) using the NWS Rothfusz equation. Enter temperature and relative humidity to get the apparent temperature and heat safety warnings.

Calculate your ideal body weight using four evidence-based formulas (Devine, Robinson, Miller, Hamwi) plus a BMI-based healthy weight range.

Plan your intermittent fasting schedule with a visual countdown timer. Supports 16:8, 18:6, 20:4, and OMAD protocols. Set your fast start time and track your eating window.

Calculate lean body mass (LBM) using the Boer, James, and Hume formulas from weight and height. Includes fat-free mass estimate for male and female.

Calculate daily protein, carbs, and fat grams from your calorie target using common macro splits.

Estimate your one-rep max (1RM) from any weight and rep count using five formulas (Epley, Brzycki, Lombardi, O'Conner, Wathan). Includes a rep-weight table. Free and private.

Predict your ovulation date and fertile window based on your last period and cycle length. See up to 6 cycles at once. Free, private, no sign-up.

Calculate running pace, finish time, or distance. Enter any two values and get the third, plus split times for 5K, 10K, half marathon, and marathon. Free and private.

Track your menstrual cycle, predict your next period, ovulation date, and fertile window. All data stays in your browser.

Convert your dog or cat's age to the equivalent human years. Accounts for breed size (small, medium, large, giant dogs) and follows AKC / AAFP age conversion guidelines.

Calculate how much to feed your dog or cat each day based on weight, activity level, and life stage. Uses the standard veterinary RER/MER energy formula.

Calculate your estimated due date from your last period, conception date, ultrasound, or IVF transfer. Shows gestational age, trimester, and key milestones. Free and private.

Calculate recommended pregnancy weight gain based on pre-pregnancy BMI using IOM (Institute of Medicine) 2009 guidelines. Track whether you are on track each trimester.

Predict your finish time for any race distance based on a known race result. Uses Riegel's formula for 5K, 10K, half marathon, marathon, and more.

Calculate your running stride length from cadence (steps per minute) and pace, or find the cadence needed for a target stride length. Improve running efficiency.

Calculate optimal wake-up or bedtimes based on 90-minute sleep cycles. Wake between cycles to feel refreshed. Choose from 3 to 6 complete cycles.

Log your bedtime, wake time, and sleep quality each day. Track average sleep duration and quality trends over time. All data is stored locally in your browser.

Calculate how long sunscreen protects your skin based on your Fitzpatrick skin type, SPF rating, and UV index. See how much sunscreen to apply and when to reapply.

Calculate UK alcohol units and US standard drinks for any drink. Enter volume and ABV, or pick from common drink presets. Includes low-risk drinking guidelines.

Convert step count to distance in km, miles, meters, or feet, or find out how many steps you need to walk a given distance. Estimates stride length from your height and gender.

Calculate your personal sweat rate and post-exercise rehydration target. Weigh yourself before and after a workout to get a precise fluid replacement plan.

Calculate swim pace per 100m or 100y, total swim time, or distance. Supports pool and open-water distances.

Convert treadmill speed (km/h or mph) to running pace (min/km or min/mile) and back. Includes incline grade-adjusted pace calculation.

Enter the UV index and your Fitzpatrick skin type to calculate safe sun exposure time, vitamin D production time, and the recommended SPF sunscreen rating.

Estimate your VO₂ max from the Cooper 12-minute run, 1.5-mile run, or Rockport 1-mile walk test. Includes ACSM fitness category rating.

Calculate your waist-to-height ratio (WHtR) to assess cardiovascular and metabolic health risk. Research shows WHtR may be a better predictor of health risk than BMI alone.

Calculate your waist-to-hip ratio (WHR) and see your cardiovascular health risk category (low, moderate, high) according to WHO guidelines. Supports inches and centimetres.

Calculate your Wilks score to compare powerlifting strength across different body weights. Enter body weight and total (squat + bench + deadlift).

Calculate the wind chill temperature using the NWS formula. Enter air temperature and wind speed to get the feels-like temperature, frostbite risk time, and safety recommendations.

Calculate total workout volume (sets × reps × weight) for each exercise and your full session. Track total tonnage and estimated one-rep max.