Health & Fitness
125 free health & fitness tools in the Calculators & Converters collection — every one runs in your browser with no signup and no uploads. Page 1 of 2.
BMI / BMR / TDEE Calculator
Body mass index, basal metabolic rate and daily calorie needs in one tool.
Calorie Calculator
Estimate your daily calorie needs for maintenance, weight loss or gain using Mifflin–St Jeor.
Aquarium Protein Skimmer Sizing Calculator
Match protein skimmer rated volume to your actual bioload
Basketball Salary Cap Space Calculator
Calculate remaining NBA cap space from contracted salaries.
Beer Calories & Carbs Calculator
Estimate calories and carbohydrates per serving from OG and FG
Beer-Lambert Protein Concentration Calculator
Quantify protein concentration from absorbance and an extinction coefficient
Bellows & Extension Tube Exposure Calculator
Calculate exposure increase and magnification for bellows and tubes
Adult BMI Calculator & WHO Classification
BMI from height and weight with underweight to obese classification
Pediatric BMI Percentile Calculator (CDC)
Age- and sex-adjusted BMI percentile for children 2-20
Spaced Repetition Review Interval Calculator
Calculate spaced repetition review intervals for exam prep.
Lean Body Weight Calculator (Janmahasatian)
LBW for drug dosing in obese and normal-weight patients
Close-Up Lens Diopter Calculator
Find magnification and focus distance for close-up filters
Macro Lens Working Distance Calculator
Calculate working distance from front element to subject at any magnification
Cardiovascular Lipid Risk Calculator (Framingham)
10-year CVD risk from lipid panel, age, sex, BP, and smoking
Macro Focus Stacking Step Calculator
Calculate focus step distance for complete depth-of-field coverage in macro stacks
Pet Body Condition Score Calculator
Estimate your dog or cat's body condition score from a quick check
Pet Gestation & Due Date Calculator
Calculate expected due date for dogs, cats, rabbits, and guinea pigs
Powerlifting DOTS Score Calculator
Calculate your DOTS coefficient score for fair lift comparison.
Powerlifting One-Rep Max Calculator
Estimate your 1RM from any submaximal set.
Powerlifting Wilks Score Calculator
Calculate your Wilks score to compare lifts across bodyweights.
BCA / Bradford Protein Assay Standard Curve Calculator
Fit a protein standard curve and read off unknown concentrations
Protein Yield & Recovery Calculator
Track total protein, activity, and purification fold across fractions
Rowing Ergometer Calorie Calculator
Calculate calories burned on a rowing machine from split time.
Boston Marathon Qualifier Checker
Check if your marathon time qualifies for Boston by age group.
Running Cadence & Stride Length Calculator
Calculate your running cadence from pace and stride length.
Running Calories Burned Calculator
Estimate calories burned running any distance at your weight.
Running Heart Rate Zone Calculator
Calculate your 5 running heart rate zones from max HR.
Running Hill Grade Pace Adjuster
Adjust your target running pace for hills using Minetti.
Running Negative Split Pace Calculator
Plan a negative-split race from gun to tape.
Running Power Zone Calculator
Convert your critical power to 5 running power zones.
Running Race Time Predictor
Predict your race time at any distance from a recent result.
Running VO2max Estimator
Estimate your VO2max from a timed run or race result.
Body Fat % Calculator (US Navy Method)
Estimate body fat percentage using the US Navy circumference formula.
Athlete Lean Bulk / Cut Calorie Calculator
Set your daily calorie surplus or deficit for body-composition change
Athlete Macro Calculator
Calculate protein, carb, and fat targets for sport performance
Athlete Protein Timing Calculator
Distribute protein intake optimally across training-day meals
Sleep & Athletic Performance Calculator
Estimate how sleep debt is taxing your athletic output
Cycling VO2max Estimator
Estimate your VO2max from a cycling FTP or ramp test.
Rowing VO2max Estimator
Estimate VO2max from a 2K erg time.
Bread Hydration Calculator
Baker percentages for water, salt and total dough
Running Pace Calculator
Enter distance and time to get your pace and projected race times.
Macro Split Calculator
Turn a calorie target into grams of protein, carbs and fat.
BMR Calculator
Your Basal Metabolic Rate with the Mifflin-St Jeor equation.
TDEE Calculator
Total Daily Energy Expenditure from BMR and activity level.
Body Fat Calculator
Estimate body fat percentage with the US Navy method.
Lean Body Mass Calculator
Lean mass and fat mass from the Boer formula.
Calorie Deficit Calculator
Find your daily calorie target for steady, safe weight loss.
Macro Calculator
Split your daily calories into protein, carbs and fat in grams.
Water Intake Calculator
Estimate how much water to drink each day for your body and activity.
One Rep Max Calculator
Estimate your 1RM and training weights from a set you can do.
Sleep Cycle Calculator
Find the best bedtime or wake-up time around 90-minute cycles.
Joules to Calories Converter
Convert J to cal instantly — 1 cal = 4.184 J. Free, browser-only tool.
Pregnancy Week Tracker
See how many weeks pregnant you are, your trimester and your due date.
Calorie Burn by Activity Calculator
Estimate calories burned for any activity using MET values.
BMI Prime Calculator
Express your BMI as a ratio to the healthy-weight ceiling of 25.
Waist-to-Height Ratio Calculator
Check if your waist is less than half your height — a simple health screen.
VO2 Max Calculator
Estimate your VO2 max from resting HR, a Cooper run or a Rockport walk.
Waist-to-Hip Ratio Calculator
Divide waist by hip and see your WHO health-risk band.
Protein Intake Calculator
How much protein per day for maintenance, muscle gain or fat loss.
Running Pace Converter
Convert between min/km, min/mile, km/h and mph instantly.
Pregnancy Weight Gain Calculator
Check your pregnancy weight gain against IOM guidelines by week.
Calories In vs Out Calculator
See your daily calorie balance and projected weight change.
Joules to Food Calories Converter
Convert joules to nutrition-label Calories (kcal) and back.
Calories to Joules Converter
Convert small (gram) calories to joules and back, exactly.
Target Heart Rate Zone Calculator
Training zones by Karvonen or percentage of max HR.
Calories Per Meal Planner
Split your daily calorie target across meals.
Steps to Calories Calculator
Convert your step count into calories burned.
Pregnancy Trimester Calculator
Find your trimesters, due date and gestational age.
BMI-for-Age Percentile Calculator
Child & teen BMI percentile using CDC growth charts.
Marathon Time Predictor
Predict your marathon finish from a recent race using the Riegel formula.
VDOT Running Calculator
Find your VDOT fitness score from any race time (Daniels–Gilbert model).
Calories to Kilojoules Converter
Convert food calories (kcal) to kilojoules, both directions.
Kilojoules to Calories Converter
Convert kilojoules to food calories (kcal), both directions.
Heart Rate Recovery Calculator
How fast your pulse drops after exercise.
Pace Per Kilometer Calculator
Turn distance and time into min/km, min/mile and km/h.
Daily Calorie Cycling Calculator
Split your weekly calories into high and low days.
Hydration Reminder Calculator
Your daily water target and a drink-every-X-minutes schedule.
Workout Program Builder
Build a weekly training split, track sets and reps, and export a printable PDF.
Macro Meal Planner
Plan a day of meals, hit your protein, carb and fat targets, export the plan.
Workout Log
Track sets, reps and weight per session — with history and personal-best highlights.
BMR & TDEE Calculator
Find your BMR, daily calorie burn and goal calorie targets in seconds.
Calorie & Macro Daily Tracker
Log foods against calorie and macro targets with live progress rings.
Body Fat Calculator (US Navy Method)
Estimate body fat % from a tape measure using the US Navy formula.
Sleep Cycle Calculator Pro
Bedtime, wake-up and nap times tuned to your own 90-minute cycles.
Heart Rate Zone Calculator
Turn your age and resting pulse into five training zones with exact BPM ranges.
One Rep Max Calculator (Pro)
Estimate your 1RM from seven formulas, with a full training-percentage table in kg and lb.
Water Intake Calculator (Advanced)
Personalised daily water target from weight, age, activity and climate.
BMI Calculator with Healthy Weight Range
Body mass index, your category, and the healthy weight range for your height.
Running Pace Calculator Pro: Pace, Time, Distance + Splits
Enter any two of pace, time and distance — get the third, plus splits and race predictions.
Sourdough Hydration & Baker's Percentage Calculator
Find your dough hydration and every baker's % in one click.
Pace Per Mile Calculator
Find your pace, finish time or distance — in minutes per mile.
Rowing Split Calculator
Convert your split to watts, calories and total time — or find the split you need to hit a goal time.
Steps to Miles Calculator
Convert any step count to miles and kilometres instantly.
Calories Burned Cycling Calculator
Find out exactly how many calories you burn on every ride.
Calories Burned Swimming Calculator
Find out exactly how many calories you burn for every stroke and session.
FFMI Calculator
Calculate your Fat-Free Mass Index and see how your muscularity compares.
Heart Rate Reserve Calculator
Find your true Karvonen training zones using the HRR method.
Marathon Pace Predictor
Goal time, training zones, negative splits and 5-km split cards — all from one number.
Plate Loading Calculator
Instantly know which plates to load on each side of the bar — kg and lb.
Running Cadence Calculator
Find your ideal steps per minute from speed and stride length.