Free fitness calculators
Small, focused tools for endurance and strength athletes. No sign-up, no login, deterministic maths only. Every calculator cites its primary source. They also feed into your Baseline Report if you upload your data.
Rowing
For Concept2 rowers, on-water crews and anyone chasing a 500m split.
Rowing split calculator
Convert between pace, split and distance for any rowing piece.
Open calculator →
Pace per 500m calculator
Distance and time in; split, average watts and calories out.
Open calculator →
Watts ↔ split converter
Turn Concept2 watts into a 500m split, and back again.
Open calculator →
Erg calorie calculator
Concept2 PM calorie formula with an optional weight-adjusted figure.
Open calculator →
2k predictor
Estimate your 2k from a 5k or 6k time — with the confidence caveats built in.
Open calculator →
Rowing stroke rate calculator
Metres per stroke from your split and rate, with reference stroke-rate bands.
Open calculator →
Rowing drag factor guide
Recommended Concept2 drag-factor ranges by rower type — how to set the damper.
Open calculator →
Running
For runners tracking pace, planning race times and building a training block.
Cycling
For cyclists working with power meters and threshold-based training.
Cross-sport
Calculators that apply across every discipline.
One-rep max calculator
Epley, Brzycki, Lombardi and Mayhew side by side plus their average.
Open calculator →
Training zones calculator
Five heart-rate zones and seven Coggan power zones in one place.
Open calculator →
VO₂ max calculator
Estimate VO₂ max from a 2 km row or a 5 km run, with age/sex brackets.
Open calculator →
Want the full picture across all your data? Build your Baseline.