โšก POWER ยท SPEED ยท WEIGHT-BASED

Cycling Power & Speed Calculator

Personalized estimates using your actual weight โ€” power, speed, time, and ride predictions for 10K to 160K.

๐Ÿšด CALCULATOR MODE
Kilometers (km/h)
Miles (mph)
๐Ÿšด Speed
km/h
โš™๏ธ Estimated Power
watts
โš–๏ธ Rider + Bike Weight
kg

๐Ÿ”ฌ Why weight matters + accuracy: Power to overcome rolling resistance and gravity is directly proportional to total mass (rider + bike). A heavier rider needs more watts to maintain the same speed on flats, and significantly more on climbs. Entering your actual weight makes the calculation 15-25% more accurate than using the default 80kg.

๐Ÿšด
YOUR POWER
โ€”
๐Ÿ“Š POWER REFERENCE CHART (watts)
Weight โ†“ / Level โ†’BeginnerRecreationalClubCompetitivePro

Based on typical W/kg ranges (1.5, 2.5, 3.5, 4.5, 5.5 W/kg)

โ“ FREQUENTLY ASKED QUESTIONS
โšก How is cycling power calculated from speed?โ†’
Power (watts) = aero drag + rolling resistance. Formula: 0.5 ร— ฯ ร— CdA ร— vยณ + Crr ร— m ร— g ร— v. Assumes flat terrain, calm wind, road bike position (CdA=0.3, Crr=0.005). Your weight directly affects rolling resistance term.
๐Ÿ’ช What power output is good for cyclists?โ†’
Recreational: 1.5-2.5 W/kg. Club rider: 2.5-3.5 W/kg. Competitive: 3.5-4.5 W/kg. Pro: 4.5-6+ W/kg. For an 80kg rider, that's 120-200W, 200-280W, 280-360W, 360-480W+.
๐Ÿ“ˆ Why does weight affect speed so much?โ†’
On flat terrain, weight affects rolling resistance (about 10-15% of total drag). On climbs, it's dominant โ€” a 10kg weight difference can cost 20-30 watts on a 5% grade. Our calculator includes both effects.
๐Ÿšฒ How accurate is this model?โ†’
Within ยฑ10% for typical road bikes on flat pavement. Accuracy improves with correct weight input. Real-world factors like wind, drafting, tire pressure, and rider position cause variations.