Data & method
Every page on this site defers to this one.
The anchors
Two things on this site are quoted, not estimated: the safe minimum internal temperatures, which are the USDA Food Safety and Inspection Service's published chart reproduced verbatim on the safe temperatures page; and the timetables FSIS itself publishes — the whole-turkey weight brackets at 325°F, fresh and cured ham, and the classic fresh-meat roasting tables. Where an FSIS timetable exists, our range is it.
The derived ranges
FSIS publishes almost everything at 325°F and nothing for smokers. For every other temperature we start from the nearest published anchor and cross-check at least three independently published sources — extension services, established cookbooks and equipment manufacturers' guidance. Where the sources disagree, the range is widened to cover the disagreement; it is never averaged into a false precision. That is why our ranges are sometimes wider than a recipe blog's single number — the blog is describing one oven, and we are describing yours, sight unseen.
Why time cannot be the doneness test
Domestic ovens routinely run 25°F or more off their dial. Smokers swing with wind and ambient temperature. Two roasts of identical weight cook differently if one is longer and thinner. Bone, trussing, starting temperature and door-opening all move the finish time. Timing charts — ours included — are planning tools. The only doneness test is a food thermometer reading the safe internal temperature in the thickest part of the meat.
Pull temperature vs safe temperature
Collagen-heavy cuts (brisket, pork shoulder, chuck, lamb shoulder, ribs) are safe long before they are good — they need 190–205°F for the connective tissue to render. Pages for those cuts state both numbers and the difference explicitly, because conflating them is the most common way these cuts get ruined.
Corrections
If a figure here disagrees with a primary source, the primary source wins and the page gets fixed — tell us.