Science-based tools to help you train, fuel & race smarter.

Critical Power, Critical Speed, training zones, VO₂ intervals, CHO burn, swim pacing and more — 14 science-based calculators for bike, run and swim in one place.

Threshold-state driven training-block selection with lactate curve modeling and block simulation — see projected adaptation before you prescribe. Exports to PDF.

Dial in your exact pre-race carbohydrate targets by body weight and event type — then get a complete personalised meal plan you can download as a PDF.

Adjust your target running pace, power and heart rate for conditions warmer or more humid than you've acclimated to — so your session intensity stays true in the heat.

Enter a 3-minute and a 12-minute effort and get your Critical Power, W', pVO₂max, fiber-type mix and full bike power zones — the foundation of every bike prescription.

Given your CP and W', predict the maximum wattage your athlete can sustain over 3, 5, 10, 20, 30, 60-minute (or custom) intervals — for prescriptions and race pacing.

Prescribe VO₂ max intervals on the bike with exact target watts, work/rest ratios and session totals — built from Critical Power and W' inputs.

A full breakdown of bike power zones with sub-zones (Sweet Spot, Z2 high/low, anaerobic tiers) — from one CP input, ready to drop into your training plan.

Build strength-endurance prescriptions at low cadence — target watts and cadence windows adjusted from your Critical Power for a purposeful high-torque session.

Enter a 3-minute and a 12-minute run effort and get your Critical Speed, D', vVO₂max and full run pace zones — the run equivalent of Critical Power.

Given Critical Speed and D', predict the best pace your athlete can sustain over standard or custom interval durations — essential for track sessions and race pacing.

Prescribe VO₂ max run intervals with exact target paces, work/rest ratios and session totals — built from Critical Speed and D' inputs.

Enter two swim time-trials (e.g. 400m and 200m) and get your swim Critical Speed, D' and full swim pace zones — anchor every pool set in real thresholds.

Plan swim sets with target split times per 50m / 100m across different zones — converted directly from your swim Critical Speed.

Estimate carbohydrate burn rate (g/hr) for a bike session by duration and intensity factor — the starting point for in-session fueling strategy.

Estimate carbohydrate burn rate (g/hr) for a run session by duration and intensity — essential for long-run and race-day fuel plans.

Estimate carbohydrate burn rate (g/hr) for a swim session by duration and intensity — useful for long open-water sets and triathlon fueling plans.

One-stop reference: enter CP, CS or LTHR and get a clean zone chart for bike power, run pace, swim pace and heart rate — plus HR calibration to Critical Power.