How We Calculate Every Conversion
Every conversion value on KitchenConvert is sourced from an established culinary reference and stated on the relevant page. This page explains exactly how.
Primary Data Sources
- King Arthur Baking’s ingredient weight chart — the most widely cited professional baking reference for gram weights per cup.
- USDA FoodData Central — used where a King Arthur figure isn’t available.
- BBC Good Food — used for UK-specific ingredients and measurements.
- Manufacturer specifications — used for specific branded products, such as certain nut flours, where the manufacturer’s tested weight is more precise than a generic reference.
The Spoon-and-Level Standard
Unless an ingredient page states otherwise (such as packed brown sugar), all dry volume measurements assume the spoon-and-level method: the ingredient is lightly spooned into the cup and levelled with a flat edge. Scooping directly from the bag compresses the ingredient and can add 25–30% extra weight — which is exactly why we specify the measurement method on every ingredient page.
The Australian Tablespoon
Australia is the only major English-speaking market using a 20ml tablespoon; the US, UK, and Canada use 15ml. That’s a 33.3% difference (20 ÷ 15 = 1.333). For most ingredients this is trivial, but for leavening agents like baking powder it can visibly affect a bake — which is why every tablespoon calculator on this site includes an explicit regional toggle rather than assuming one standard.
Rounding Rules
Gram weights are rounded to the nearest whole gram to stay practical for a home kitchen scale. Cup and spoon fractions are rounded to common culinary fractions (¼, ⅓, ½, ¾) or two decimal places.
What We Don’t Do
We don’t invent or estimate density values — every figure has a named source. We don’t apply one blended average across measurement methods, since that would be accurate for neither. And we don’t guarantee a specific cooking outcome, since results depend on many factors beyond measurement accuracy alone. If you spot a value that looks wrong, tell us via the contact page, including the ingredient, the value you believe is correct, and your source.