[h=3]How accurate is the elevation on my Edge 510, 520, 800, 810, 1000, and Edge Touring Plus?[/h]

The Edge 510, 520, 800, 800, 810, 1000 and Edge Touring Plus calculate elevation data using a barometric altimeter. Once the device is properly calibrated, the standard area of accuracy will be +/- 10 feet. To ensure that elevation data is accurate at the beginning of an activity, calibrate the elevation manually.

To calibrate the elevation manually:

Touch setup menu (tools icon) from the home screen
Touch System
Touch GPS
Edge Touring Plus:
Select Mark Location*
Select Change Elevation
Set elevation to known elevation of starting point
Select check-mark to save

To calibrate the elevation manually on Edge 520:

Press enter/select (upper right) button from the home screen
Press enter/select
Select Set Elevation
Set elevation to known elevation of starting point
Select check-mark to save

The elevation will then be calibrated from this manually set elevation.

The barometric altimeter is not temperature compensated. Temperature changes in the measuring device will affect the barometric pressure sensor and altimeter readings.

https://support.garmin.com/support/searchSupport/case.faces?caseId={df7142e0-ea50-11e0-73d0-000000000000**

The aviation industry has always used barometric pressure to measure altitude. Altimeters measure pressure and are calibrated to indicate that pressure as an altitude in feet or metres. The calibration assumes that the pressure drops at a standard rate as altitude is gained. We are interested in the altitude above ground level (AGL) or above mean sea level (AMSL) or with respect to the standard reference of 1013.25 hPa (Pressure Altitude, or PA). There is no evidence to suggest the industry will move to GPS altitude in the near future. - See more at: GPS and altitude for hang gliding and paragliding | Cross Country Magazine