Originally Posted by

**gregf83**
It's particularly accurate on approx 1 hr steep climbs where you go all out.

That's about right. Because with that, it's just math to get very close to a metered FTP. So long as Strava has accurate variables to work with (rider height and weight, bike weight, cadence, etc) and the ride is a steady output up a constant grade for a reasonably long period, the Strava power guesstimate can get pretty close.

Now the Strava "estimated power" over a typical ride under normal conditions? Might as well be a random number generator.