Science-backed tools for every athlete
Calculate your running pace, strength standards, heart rate zones, and body composition — with formulas validated by sports scientists.
Validated Formulas
Our calculators use the Mifflin-St Jeor equation, Karvonen formula, and Brzycki equation — the same methods used in clinical sports science.
Metric & Imperial
Switch seamlessly between US Standard and Metric. Whether you track pace per mile or VO2 Max, our tools adapt to your preferences.
Every Level Welcome
From first 5K to Boston qualifier, from gym beginner to competitive cyclist — our 3,000+ tools help every athlete train with confidence.
One Rep Max Calculator
Calculate your estimated 1RM (One Repetition Maximum) for squat, bench press, and deadlift based on your reps.
Vertical Jump Power Calculator
Estimate your vertical jump height and peak explosive power using the Sayers Formula.
Strength Standards Calculator
Compare your lifts against other lifters at your bodyweight. Are you a beginner, intermediate, or elite lifter?
Wilks Score Calculator
The standard formula used in powerlifting to compare strength across different bodyweights.
Relative Strength Calculator
Calculate your strength-to-weight ratio. Crucial for calisthenics, gymnastics, and rock climbing.
Heart Rate Zone Calculator (Karvonen)
Calculate your optimal target heart rate zones for fat burning and endurance training using the precise Karvonen formula.
BMR & TDEE Calculator
Calculate your Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE). The first step to any weight loss plan.
BMI Calculator
Check your Body Mass Index (BMI) instantly. A simple screening tool for weight categories.
Body Fat Calculator (Navy Method)
Estimate your body fat percentage without calipers. Based on the accurate US Navy formula using tape measurements.
Waist-to-Hip Ratio Calculator
Assess your fat distribution pattern and health risks. Are you an "Apple" or a "Pear"?
Ideal Weight Calculator
Find your medically recommended healthy weight range based on height and gender.
VO2 Max Estimator (Cooper Test)
Estimate your VO2 Max and cardiovascular fitness level using the 12-Minute Run Test (Cooper Test).
Bench Press Calculator
Calculate your bench press one-rep max and get personalized training percentages for strength, hypertrophy, and power.
Squat Calculator
Calculate your squat one-rep max from any weight and rep combination. Includes strength standards and training percentages.
Deadlift Calculator
Calculate your deadlift one-rep max from any working set. Includes strength standards, technique cues, and training percentages.
Sleep Cycle Calculator
Find the best bedtime or wake-up time based on 90-minute sleep cycles to wake up refreshed and optimize athletic recovery.
Electrolyte Loss Calculator
Estimate sodium, potassium, and magnesium lost through sweat during exercise and calculate your electrolyte replacement needs.
Training Pace Calculator
Input any distance and time to calculate your pace per km/mile, speed, and splits.
Marathon Pace Calculator
Calculate your marathon finish time and average pace per mile/km.
Half Marathon Pace Calculator
Plan your race pace for 13.1 miles. The perfect balance of speed and endurance.
Sub-3 Hour Marathon Pace Calculator
Calculate the exact splits needed to break the elusive 3-hour marathon barrier.
Boston Marathon Qualifier Calculator
Find out the pace you need to qualify for the prestigious Boston Marathon based on your age and gender.
5K Pace Calculator
Calculate your pace for a 5K race. Ideal for beginners and speed training.
10K Pace Calculator
Find your target pace for a 10K race. The bridge between speed and long distance.
Marathon Race Predictor
Predict your Marathon, Half Marathon, or 10K finish time using Riegel's Formula based on your best recent race result.
Marathon Fueling Calculator
Calculate gel timing, carb targets, and hydration strategy for your marathon finish time.
Rowing Pace Calculator
Convert 2K row time to training zone splits, watts, and pace targets for indoor rowing.
Bike Gear Ratio Calculator
Calculate gear ratios, gear inches, and speed at cadence for road, MTB, and gravel bikes.
FTP Calculator (Functional Threshold Power)
Calculate your Functional Threshold Power (FTP) from a 20-minute test and set your cycling training zones.
Cycling Calorie Calculator
Calculate calories burned cycling based on your weight, speed, and duration.
VAM Calculator — Cycling Climbing Speed
Calculate VAM (vertical ascent meters per hour) and estimate W/kg power output for any cycling climb.
Cycling Power Output Calculator
Calculate your cycling power output (watts) from speed, gradient, and body weight. Understand the physics of cycling performance.
Cycling VO2 Max Calculator
Estimate your cycling VO2 max from an FTP test or time trial result. Understand your aerobic ceiling and training zones.
Triathlon Pace Calculator
Calculate split targets for swim, bike, and run legs across sprint, Olympic, 70.3, and Ironman distances.
Protein Intake Calculator
Find out exactly how much protein you need per day to build muscle, lose weight, or maintain health.
Daily Water Intake Calculator
Calculate how much water you should drink daily based on your body weight and exercise duration.
Post-Workout Recovery Calculator
Calculate the perfect ratio of carbohydrates and protein for your post-workout meal to maximize recovery.
Creatine Dosage Calculator
Calculate your optimal creatine monohydrate dosage for the loading and maintenance phases.
Keto Macro Calculator
Calculate your personalized ketogenic diet macros — fat, protein, and net carb targets — based on your body weight and goals.
Intermittent Fasting Calculator
Find your eating window, fasting start and end times for any IF protocol — 16:8, 18:6, 20:4, or OMAD.
Caffeine Half-Life Calculator
Calculate when caffeine clears your system and find the optimal pre-workout timing and sleep cutoff for your metabolism.
Race Day Nutrition Calculator
Calculate carbohydrate and fluid intake targets for marathon, half marathon, and triathlon race day fueling based on pace and duration.
Vitamin D Calculator for Athletes
Calculate your daily vitamin D3 requirement based on sun exposure, latitude, skin tone, and athletic training load.
Swim Pace Calculator
Calculate your swimming pace per 100m or 100 yards for any distance. Perfect for pool and open water training.
Swimming Calorie Calculator
Estimate calories burned swimming based on stroke, pace, and body weight.
Swim Training Zones Calculator
Calculate your five swimming training zones from CSS (Critical Swim Speed) or lactate threshold pace for structured interval training.
Open Water Swim Time Predictor
Predict your open water swim time from pool pace. Accounts for sighting overhead, wetsuit effect, and current conditions.