The USDA suggests an internal temperate of 145 degrees F plus a 3 minute rest for steak. However, cooking times and temperatures will vary based on your desired degree of doneness. I always recommend using a meat thermometer, like the meater+.  In addition, steak should be removed from the heat source when the internal temp is about 5 degrees lower than your desired level of doneness to prevent it from overcooking as it rests.  Rare - 125 degrees F Medium Rare - 135 degrees F Medium - 145 degrees F Medium Well - 150 degrees F Well Done - 160 degrees F Source: certifiedangusbeef.com