Tools & Calculators

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Small, focused tools for running with power.

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Stryd weight

The weight set on your Stryd, not today’s scale weight — it recovers the W/kg the pod measured.

CP / FTP

Critical Power, in watts. The CP calculators can save their result here.

Gender

FemaleMalePrefer not to say

The W′ check's norms are published by gender. Nothing else uses it.

Stryd pod

Stryd (non-Wind)Stryd WindOther / not sure

Never guessed from your file — the W′ norms differ by pod.

Units

CP calculators

Your critical power and W′, fitted from maximal efforts you have already run.

Fit CP and W′ from two running-power efforts — typed in, or read from your CP test .fit — and see the power-duration curve.

Fit CP and W′ across three or more maximal efforts from separate runs, with a standard error on CP and all three models compared.

The numbers a race plan is built from. Each returns one value to carry forward; none of them predicts a finishing time.

Compute RE — speed per mass-specific power — from a brushed range of a .fit file or manual numbers.

Look up a fatigue-resistance exponent from a recent race and the distance you are targeting, with the likely alternatives around it.

Convert a power measured in one set of conditions to what it would have been in another — altitude, temperature and humidity.

Every one of these needs a .fit file. The first reads one; the other three change one and hand it back to download.

Drop a .fit file to trace power, heart rate, cadence, pace, and elevation over time.

Forgot to press stop? Keep the stretch you actually ran and drop the rest.

Recorded at the wrong Stryd weight? Rescale every watt by one constant and download the corrected file.

A marathon that read 42.10 km? Rescale the distance by a factor, or land it on the course length.