Speed not accurate

Am I the only one that noticed that the speed shown in the Zwift app is not even close to the speed one is traveling? I’ve checked my spindown multiple times, but when I am doing say 16MPH (based upon gearing and cadence), the MPH value that shows on the screen is often not even close to the speed at which I know I am traveling. I am using a Wahoo Kickr Snap and have used it a total of 3 times with the same results. This is not a problem per say, just an observation and may be due to my setup.

Speed within Zwift is determined by your watts, weight entered, in-game bike used, in-game drafting, and virtual elevation changes.

Zwift and the speed your trainer reports are not the same. Zwift calculates speed based on power, gradient, weight etc whereas your trainer just uses flywheel speed. You can’t compare the 2.

For example when you do a workout in ERG mode and have your chain on the small chainring doing 200 watts the speed your trainer reports will be slower than the speed it reports when doing the same power but with the chain on the large chainring (same cog on the back). The only difference being the flywheel speed. Your speed on Zwift will be the same.

Got it. Thanks, for your quick reply Nigel.