Methodology

Every figure on PantryMetric traces back to a specific, checkable source. This page documents exactly which sources, so any number on the site can be verified rather than taken on faith.

Ingredient density (grams per US cup). Sourced primarily from King Arthur Baking Company's published "Ingredient Weight Chart" — a commonly cited baking-industry reference — cross- checked against USDA FoodData Central (fdc.nal.usda.gov) for produce, dairy, and grain reference weights. Flour and starch figures use the spooned-and-leveled measurement convention (not scooped-and-packed, which reliably over-measures). An ingredient without a reliable density figure from either source is omitted from the converter rather than assigned a guessed value. Fixed unit conversions (1 US cup = 236.588 ml = 16 tbsp = 48 tsp; 1 oz = 28.3495 g) are standard unit facts, not ingredient-specific claims.

Storage and shelf life. Sourced exclusively from USDA FoodKeeper data and USDA FSIS (Food Safety and Inspection Service) fact sheets, dated 2026-07-12. These figures are on an annual-refresh cadence — checked again roughly once a year, since USDA guidance is occasionally revised. No storage duration on this site is invented or estimated from general knowledge.

Safe minimum cooking temperatures. Sourced directly from USDA FSIS published minimum internal cooking temperature guidance, including the required rest time where FSIS specifies one (e.g. the 3-minute rest for whole cuts of beef, pork, veal, and lamb at 145°F). These are safety-critical figures and are never adjusted, rounded loosely, or approximated.

Substitutions. Bounded to ingredients with a well-established, commonly recommended substitute relationship — each with a specific ratio and an honest note on how the result differs in texture or flavor. An ingredient without a real, cook-tested substitute is left off the substitution index rather than given a weak or invented one.

Oven temperature / gas mark conversion. The UK/EU gas mark table and the standard fan/convection oven adjustment (-25°F / -20°C from a conventional recipe temperature) follow standard published UK gas-mark conversion tables, cross-checked against King Arthur Baking's oven temperature chart.

Pan size conversion. The area-ratio math (comparing round-pan and rectangular-pan areas) is exact geometry. The suggested bake-time and temperature guidance is a documented rule of thumb from general baking-reference sources, presented as guidance with the underlying area-ratio math shown — never false precision.

Testing. The underlying conversion library (density conversion, recipe-scaling fraction rounding, temperature conversion, and pan-area scaling) ships with an automated Vitest test suite, so a change to the shared logic can't silently break a tool that depends on it.

Data freshness. Storage and safe-temperature data are dated 2026-07-12 and reviewed on an annual refresh cadence, since USDA guidance is occasionally revised.