Free endurance calculators
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Endurance calculators
Triathlon Pace Calculator
Calculate swim, bike, run and transition splits to estimate your triathlon finish time.
Open Triathlon Pace CalculatorFTP & Cycling Power Zones Calculator
Calculate FTP, seven cycling power zones, sweet spot and watts per kilogram.
Open FTP CalculatorCritical Swim Speed Calculator
Calculate CSS pace from 400 m and 200 m swim time trials, with metre and yard equivalents.
Open CSS CalculatorRunning Race Time Predictor
Predict an equivalent 5K, 10K, half marathon or marathon time from one completed race result.
Open Running Race Time PredictorTriathlon Race Nutrition Planner
Turn your own carbohydrate, fluid and sodium targets into bike and run totals and timing.
Open Triathlon Race Nutrition PlannerTraining guides
Swimming
Critical Swim Speed (CSS) test: how to do it and use the result
How to run the 400 m and 200 m CSS swim test, calculate your pace per 100 m, and use it to set swim sets and race pace.
Read the guideWhat is a good CSS swim pace?
Typical Critical Swim Speed (CSS) paces per 100 m by level and age, and how to read your own result.
Read the guideFrom pool to open water: why you feel out of air even with a good CSS
Why a good pool swimmer can struggle to breathe in open water, how CSS relates to open-water swimming, and a safe way to build up.
Read the guideCycling
FTP test and power zones: how to test, calculate and use them
How to run a 20-minute or ramp FTP test, what the result means, and how to turn FTP into seven power zones, sweet spot and W/kg.
Read the guideFTP test: ramp vs 8-minute vs 20-minute
Compare the ramp test, the 8-minute test (×0.90) and the 20-minute test (×0.95) for estimating FTP, with when to use each.
Read the guideFTP watts per kilo (W/kg) by level
What a good FTP in watts per kilogram looks like, with Coggan power levels and percentile data from thousands of riders.
Read the guideWhy your heart rate and power zones don't match
Why Garmin, Strava and your power meter give different zone 2 numbers, how heart rate and power zones are built, and how to pick one to train by.
Read the guideWhat bike to buy for your first triathlon
Road bike or tri bike for a first triathlon? Compare clip-on aero bars, buying second-hand, frame size and budget, and see what a faster bike split is worth.
Read the guideRunning and racing
Average triathlon times by distance
Average and top-20% finish times for sprint, Olympic, 70.3 and Ironman triathlons, with notes on what the numbers measure and how to use them.
Read the guideIronman 70.3 pacing strategy: swim, bike and run
A practical pacing plan for a half-distance triathlon, with an example 5:30 split table and how to avoid the classic bike and run mistakes.
Read the guideWill I make the cut-off? How to check your margin in a 70.3 or Ironman
How swim, bike and finish cut-offs work in a 70.3 or Ironman, why each race has its own rules, and how to check your margin with your split times.
Read the guideBrick workouts: how long to run after the bike, and why
What a brick workout is for, how long the run should be for transition practice, pace work or race rehearsal, and how often to do bricks.
Read the guideNutrition
70.3 race nutrition: carbohydrates, fluid and sodium per hour
How many carbohydrates, how much fluid and how much sodium to plan per hour in a half-distance triathlon, with a worked example.
Read the guideSprint and Olympic triathlon nutrition
How much carbohydrate, fluid and sodium to plan for a sprint or Olympic triathlon, based on race duration and sports-nutrition guidance.
Read the guideGetting started
Ironman vs T100: how the two race series compare
Ironman vs T100 compared: distances, format, age-group qualification (Kona slots vs T100 World Championship), entry costs and which race suits you.
Read the guideTriathlon training with a full-time job and a family
How to fit triathlon training around work and family: priorities, example weeks for 6, 8 and 10 hours, and what to do when a session is missed.
Read the guideBuilt for endurance athletes
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