Power-to-Weight Ratio Calculator

Power-to-weight ratio (W/kg) is the ratio of an athlete's peak power or functional threshold power to their body weight. In cycling, it determines how quickly a rider can climb hills. A W/kg of 4.0 at FTP is considered well-trained amateur level; professional climbers often exceed 6.0 W/kg.

British Cycling and TrainingPeaks use the following categories based on 20-minute FTP W/kg: Cat 5 (novice) below 2.0, Cat 4: 2.0-2.5, Cat 3: 2.5-3.5, Cat 2: 3.5-4.5, Cat 1: 4.5-5.5, Elite/Pro: above 5.5 W/kg. These are rough guides and actual racing categories depend on race results.

The W/kg equation means both approaches improve the ratio equally from a mathematical standpoint. However, reducing weight beyond a healthy body fat level impairs health and often reduces absolute power. In practice, increasing power through training is the healthier, more sustainable route for most athletes.

Yes. Power-to-weight ratio is important in any sport where the athlete must propel their body weight: running, jumping, gymnastics, rock climbing, and martial arts all reward athletes with a high power-to-weight ratio. In these sports, W/kg is estimated from vertical jump tests or sprint tests rather than a power meter.

Without a power meter, peak anaerobic power can be estimated from vertical jump height using the Sayers equation (see the vertical jump power calculator). Dividing this power in watts by body weight in kilograms gives a W/kg estimate. For FTP estimation, a 20-minute test on a calibrated stationary bike with power display is the most accessible method.