Power meters are special sensors installed on a bicycle that gauge the amount of power used to propel it forward. These sensors provide high-quality data, which the Strava app can collect using a wireless medium such as ANT+ or Bluetooth LE. For some phones, additional hardware is required to use these wireless protocols.
When data from a power meter is not available, Strava estimates power using information about athlete's weight, speed, and elevation change. For more info see Power Calculations.
In order for Strava to calculate your watts, you'll need three things:
- A bike attached to your ride. If you have no bikes on Strava or do not attach a bike to your ride a default road bike weight of 9kg, or approximately 20lbs, will be used instead. See Gear for more help.
- Your personal weight listed in your Account Settings, see Personal Settings for help.
- Trusted elevation numbers - from either a device with a barometric altimeter, like a Garmin Edge 500 or from our internal elevation correction. See Elevation for your Activity for more information.
To ensure power estimates are as accurate as possible, make sure you have accurate weight data for your bike, and yourself. Make sure you include the weight of your clothes (helmet, shoes etc) tools and other gear and supplies.
Average power gives your average power amount during the ride, expressed in Watts (a measure of how much energy you are placing into the pedals.) This is inclusive of the entire ride, and so it takes coasting into account as well. Average power is most accurately measured by a power meter, though if you don't have a power we give a rough approximation through our power estimator.
Strava's servers start generating the power analysis for Premium users when you upload, but the reports may not be available immediately. If the report is not available for a few hours, please contact our support team.