Why WattGap
Tire rolling resistance compared at your pressure
Lab-tested Crr adjusted for your rim width, pressure, tubes and roads.
Beyond a single number
Tire rankings usually quote one pressure. WattGap uses multi-pressure lab results and adjusts for your actual setup.
Rim width matters
The same tire measures differently on different rims. Enter internal and external width, or your measured width, for a realistic figure.
Try it on your own rides
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