With traditionally cooked burgers, it is very difficult to gauge doneness. Low density means rapid overcooking and a relatively thin profile means that it's difficult to judge where to stick a thermometer. With precision cooking, you can nail that perfect pink interior time after time.Very Rare to Rare: 115°F / 46°C to 123°F / 51°C, 40 minute to 2 1/2 hoursMedium-Rare: 124°F / 51°C to 129°F / 54°C, 40 minutes to 2 1/2 hoursMedium: 130°F / 54°C to 137°F / 58°C, 40 minutes to 4 hours (2 1/2 hours max if under 130°F / 57°C)Medium-Well: 138°F / 59°C to 144°F / 62°C, 40 minutes to 4 hoursWell-Done: 145°F / 63°C to 155°F / 68°C, 40 minutes to 3 1/2 hours