Probes, leave-in thermometers and instant-reads: how accurate they are, how to calibrate them, and why the lid dial and the grate disagree.
Google's own AI Overview cites the USDA at two to four degrees and three other sources at one to two degrees, then leads with the smaller number without noticing they disagree. "Accurate" is standing in for four different claims: resolution, factory tolerance at one point, calibration drift, and how long you waited. A spec sheet only ever answers one of them.
Updated Sep 2026
Half this search is people asking each other, and the two results that answer plainly contradict each other. Both are right. Leaving a probe in does not make it a faster instrument, it puts it in a different thermal situation, and the error changes sign.
Updated Sep 2026
Every authority page on this search teaches the ice water test and stops there. Ice water finds one kind of error. A smoker lives two hundred degrees away from it, and the error that matters most out there is the one a single fixed point cannot see.
Updated Sep 2026
Google's own answer box gives the gap between a lid dial and a grate probe as fifty to a hundred degrees, twice, with the sign reversed. Six results, three different signs. That is not a hard question. It is a question with no fixed answer, being answered as though it had one.
Updated Oct 2026