Watt ↔ Speed: Why a calculator gives you instant clarity

You’ve probably felt it: you’re pushing “good watts”, but the speed doesn’t match. Or you’re flying and wonder how much power that actually costs.

That’s exactly what our Watt ↔ Speed Calculator (no wind) is for.

👉 Try it now: Watt ↔ Speed Calculator

You can use it in two directions:

  • Watts → Speed: enter power and get the predicted speed.
  • Speed → Watts: enter a target speed and get the required power.

The key benefit: it also shows how the resistances split—so you can see where to optimize.

What the calculator includes (compact)

  • Aerodynamics (CdA): the biggest lever at higher speeds.
  • Gradient: dominates on climbs—small speed changes can cost a lot of watts.
  • Air density (ρ): derived from temperature and altitude (optional sea-level pressure). Denser air means more aerodynamic drag.
  • Rolling resistance (Crr): included via a simplified dropdown to keep comparisons fast.
  • Drivetrain efficiency (η): optional step between pedal power and wheel power.

No wind—so you can compare setups and scenarios cleanly.

How to use it (no nerd overload)

1) Pick a mode

  • Watts → Speed for training/race planning (“What happens at 230/260/300 W?”)
  • Speed → Watts for targets (“How many watts do I need for 38 km/h?”)

2) Set CdA realistically

If you’re unsure, start with a conservative option (e.g. “Standard”), then test variations.

Tip: if you want the deeper why behind aero, read: Aerodynamic drag in cycling – the invisible brake

3) Use it for decisions, not just a number

The real power is comparison:

  • How much do you gain from “tucked down” vs “standard”?
  • What does +1% gradient cost at the same speed?
  • How does cold air or altitude change the outcome?

That’s how “feel” turns into a plan.

Takeaway

The Watt ↔ Speed Calculator is a fast reality check for training and racing:

  • See what speed matches your watts.
  • Understand why (aero, gradient, air density).
  • Compare setups and strategies in seconds.

👉 Open the calculator: Watt ↔ Speed Calculator

Want the next step? RaceYourTrack combines the calculator with GPX/TCX analysis, simulation and TrackIQ—so you get more depth, saved setups and detailed insights.