You can try the finger-poke test or the “snap” test, but a digital meat thermometer is your best friend. Insert it into the end of the brat, avoiding the casing, and look for 160°F. Pull them off at 155°F if you like them extra juicy—carryover heat will take them the rest of the way.
Here’s a cultural tidbit: in Wisconsin, the unofficial brat capital of America, locals say you should never use a fork to turn brats. Why? Puncturing them releases the precious juice. Use tongs. Gentle tongs.
Fun fact: bratwurst is so iconic in Wisconsin that the state’s official motto might as well be “sizzle with purpose.” There’s even a “Brat Fest” in Madison that serves over 200,000 brats every year. They know how long to cook them—and they’re not telling.
