Potência Aprox = v³
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
About this calculator
This calculator estimates the power required to maintain a constant cycling speed using the formula W ≈ 0.0036·v³, where v is velocity in km/h. It reflects aerodynamic power being proportional to velocity cubed. Suitable for training planning or performance comparisons, but not a substitute for precise power meter measurements.
The formula assumes air resistance proportional to v² and force proportional to v³, ignoring factors like wind, slope, and cyclist efficiency. Works best above 20 km/h. Useful for comparing efforts across segments, but for scientific or competitive use, employ more robust methods.
Caveats: excludes mechanical losses, ground resistance, and air density variations. Results may underestimate actual power in adverse conditions. Ideal for quick estimates, not advanced training prescriptions. Combine with sensor data for accuracy.
Frequently asked questions
How does the W ≈ 0.0036·v³ formula work?
Aerodynamic power depends on velocity cubed. The 0.0036 is an approximation for unit conversions and typical resistance.
What is this calculator used for?
Estimates power needed to maintain a specific cycling speed, helping plan training efforts.
Does it account for wind or slope?
No. The formula is simplified and ignores wind, hills, and cyclist efficiency.
Can I use it for competitions?
Not recommended. Results are approximations and not replacements for professional sensor data.
How do I find my ideal training speed?
Try different speeds on this calculator to compare power outputs. Combine with physiological limits and goals.