Use the hand test if you have to, but buy a $10 thermometer

The hand test (holding your palm over the grate) is the easiest, but it’s not very accurate.

To do it: hold your hand about 5 inches above the coals and count seconds. 2 seconds = high heat (~450°F+), 4 seconds = medium (~350°F), 6 seconds = low (~300°F). It works in a pinch, and you don’t need any gear. The downsides: everyone’s hand is different, wind messes it up, and you can’t get precise temps for things like indirect cooking or smoking.

If you grill more than once a month, grab a cheap instant-read thermometer. They’re like $10–15, give you the real number in seconds, and you can also check food temps with it. Way more reliable than guessing with your palm.

Spend ten bucks and never guess again.