Free performance calculators for athletes
Enter your numbers. Get answers instantly.
Calculate rowing splits, training paces, strength metrics and nutrition targets instantly — free tools you can use before every session.
Search by name, sport, or training metric.
Instant calculations
Enter your numbers and get results immediately — no sign-up required.
Evidence-based formulas
Built on established sports science methods used by coaches and athletes.
Built for athletes
The metrics you actually use in training — splits, paces, loads, and macros.
Popular Calculators
Pick a tool, enter your data, and get the result straight away.
Watts to 500m Split Calculator
Enter watts → get your split instantly
CalculateRowingTarget Split Calculator
Enter distance and time → find your required split
CalculateRowingRowing Training Zone Pace Calculator
Enter your 2k time → get training pace zones
CalculateRunningRace Time Predictor
Predict future race times from a recent performance
CalculateStrength1RM Calculator
Enter weight and reps → estimate your max
CalculateNutritionMacro Calculator
Enter body stats → get daily macro targets
CalculateCalculator Categories
Browse by sport — each category groups the calculators you reach for most often.
Rowing
Splits, watts, and erg pace — the numbers rowers check every session.
View calculatorsRunning
Race predictions, training paces, and zones from your recent efforts.
View calculatorsStrength
1RM estimates, plate math, and relative strength from your working sets.
View calculatorsNutrition
Macro splits and calorie targets based on your body and training load.
View calculatorsWhy use these calculators?
A straightforward set of tools for the training numbers you need every week.
Accurate formulas
Each calculator uses well-established equations from rowing, running, strength, and nutrition science.
Fast results
No loading screens or accounts. Type in your data and see the answer in seconds.
Built around real training metrics
Splits, watts, VDOT paces, 1RM estimates, and macro targets — the numbers you track week to week.
Need a number before your next session?
Open a calculator, plug in your data, and get the answer — no account, no waiting.
Go to Calculators