Power-to-Weight Ratio Calculator

Your power-to-weight ratio is the single greatest determinant of performance. Its not everything but greater than all else.  Power to weight is the average power output for a select duration over your body weight, in kilograms.  Numerator over denominator: watts/ kilogram.  Most often times, power to weight is expressed as one's threshold power over their body weight. 

The more power a cyclist can make relative to their body size the faster they can ride uphill.  Power-to-weight ratio has less of an affect for flatter ride such as time trialling where power to your aerodynamic drag, matters the most.  Drag is expressed as CdA (coefficient of drag) and the ratio is power / CdA.


Using the power-to-weight ratio is a way to compare riders of different body sizes  If your FTP is 250 watts and you weigh 50kg, that's a power-to-weight ratio of 5.0 w/kg (which is really fast).  On the other hand, if your FTP is 250 watts with a body size of 75 kg, that's a power-to-weight ratio of 3.33 w/kg, which is 33% slower than the 50kg rider with the same FTP. 

Zwift categories are listed above but other common benchmarks are the following:


> 6.0 w/kg = Tour de France or World Tour Level

> 5.0  w/kg = domestic Professional

> 4.0  w/kg = really REALLY good amateur

> 3.0 w/kg = a good club rider


5.8 w/kg = Top TdF and/or Olympic Gold Medalist

> 4.5 w/kg = Professional Level

> 3.5 w/kg = really REALLY good amateur

> 2.5 w/kg = a good club rider

> 1.5 w/kg = successful masters rider

These values above come in many different durations so it is important to look at the duration expressed in order to make an apples to apples comparison.

Coach Isaiah put together a junior power profile chart looking at how junior power to weight ratio's across the 1 minute, 5 minute and 20 minute durations. 

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To talk with a FasCat Coach about improving your power to weight ratio, please fill out a New Athlete Questionnaire to set up a complimentary coaching consultation.

About Frank Overton

Frank founded FasCat Coaching in 2002 and has been a full time cycling coach since 2004. His educational background includes a Masters degree in Physiology from North Carolina State University, pre-med from Hampden-Sydney College. Frank raced at a professional level on the road and mountain bike and currently competes as a "masters" level gravel and cyclocrosser. Professionally Frank comes from medical school spinal cord research and molecular biotechnology. However, to this day it is a dream come true for Frank to be able to help cyclists as a coach.

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