Hello. 
I’ve had a Forerunner 220 for a few years now. I’m finding that every run I go on is coming up short vs. both online tools such as Gmap-pedometer.com and mapmyrun.com, and my iPhone. A 10k run can be as much as 500 metres short, so I end up running further than planned to make up the distance. 
Is there anything I can do to improve the accuracy of my Forerunner, or should I be looking to replace it? It has the latest software update. 
Thanks!
 
				 
		 
					 
				