Built-in browser for Android will not give you accurate GPS location for security reasons. Test it with different web browsers that would need permissions to get the accurate location from GPS when installed.
After switching GPS off, the data is received with < 10 meters accuracy.
Do not use Android Browser for websites, if you want to get GPS location with high accuracy.
50 meters precision can be seen for Safari browser if tested for iPhone with wifi switched off. Yes, the accuracy is lesser.