Triathlon Calculators
Free, personalised calculators for swim, bike, run, nutrition and race day
Every tool works from your own numbers, so you get an answer for your race and your paces, not a generic chart. Pick a calculator below.
Race day & cutoffs
Plan your race against the clock.
Race-Day Planner
Splits, pacing bands and a fueling plan from your CSS, FTP and LTHR — in one shareable page.
Cutoff Calculator
Will you make the swim, bike and overall cutoffs at your race?
Race Time Predictor
Estimate your finish time from your swim, bike and run splits.
Transition Time
Build a realistic T1 and T2 budget into your plan.
Wetsuit-Legal Checker
Is the swim wetsuit-legal at the forecast water temperature?
Pacing & performance
Dial in your paces across all three disciplines.
Pace Converter
Convert between min/km, min/mile and speed.
Pace Adjustment
Adjust target pace for heat and hills.
Grade-Adjusted Pace (GAP)
Find the flat effort equivalent of your hill pace.
Swim Calculator
Work out swim pace, time or distance.
CSS Calculator
Find your Critical Swim Speed from a test set.
Bike Split Estimator
Estimate your bike leg time from power and course.
Cycling Calculator
Solve for speed, power or time on the bike.
Marathon Calculator
Pace the run leg and project your marathon split.
Age-Grading Calculator
Compare your performance across ages and sexes.
Training
Set zones, manage load, and taper right.
FTP Calculator
Set your Functional Threshold Power from a test.
Training Zones
Build heart-rate, power and pace zones.
VO2 Max / VDOT Calculator
Get your aerobic fitness score from a race time or Cooper test.
Training Load
Track your weekly training load and ramp.
Taper Planner
Plan your race-week taper.
Calorie Burn
Estimate the energy cost of a session.
Nutrition & hydration
Fuel and hydrate to your own numbers, not a generic chart.
Triathlon Fueling Calculator
Carb, fluid and sodium targets per hour from your duration, intensity and conditions.
Race Nutrition Planner
Build a full race-day fuelling plan.
Carb Timing
Time your carbohydrate intake through the race.
Carb Loading
Plan your pre-race carbohydrate load.
Carb Mix
Get the drink-mix ratios for your target carbs.
Gel Shopping
Work out how many gels to buy for a race.
Electrolyte Calculator
Estimate your electrolyte needs.
Hydration Calculator
Work out your fluid needs by conditions.
Sweat Rate
Measure your sweat loss to set fluid targets.
Sodium Balance
Match sodium intake to your sweat losses.
Caffeine Calculator
Dose and time caffeine for race day.
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