Editorial standards

Every page on this site publishes a number that someone is going to put into a mixing bowl. This page explains exactly what those numbers mean, where they come from, and what we do when one of them is wrong.

What the number on each page actually is

Every ingredient page publishes one primary figure: the mass in grams of one US customary cup of that ingredient, filled by a stated method. It is a working density, not a physical constant. The same ingredient from a different brand, in a more humid kitchen, or scooped instead of spooned, will weigh something different — which is why each page also publishes a table of what the cup weighs under the other common handling methods.

Which cup we mean

“One cup” is not a single quantity, and this is the source of a large share of failed conversions:

• US customary cup — 236.588 mL. The cup in American recipes and the cup all conversions on this site are based on.
• US legal cup — 240 mL. Defined by the FDA for nutrition labelling. Most recipe sites round to this, and the 1.4 percent difference from the customary cup is smaller than the error in filling the cup at all.
• Metric cup — 250 mL. Standard in Australia and New Zealand and common in the UK. A recipe from those countries uses a cup about 6 percent larger than an American one, and an Australian tablespoon is 20 mL against the US 14.8 mL.

If a recipe's origin is unclear and the result matters, use the gram figures. Grams are the same everywhere.

Where the figures come from

The primary source is USDA FoodData Central, which publishes standardised reference measures for foods. For baking ingredients where the USDA reports only per-100 g nutrient profiles and no working household measure, we cross-check against the King Arthur Baking ingredient weight chart, which is the reference most American recipe developers calibrate to.

Source and method note carried in the dataset itself: Dry goods are spoon-and-level. Brown sugar is firmly packed. Butter assumes salted or unsalted stick butter at room temperature. Liquids are by volume, so water and water-like liquids are taken as 240 g/cup at room temperature.

How the ingredient is handled when it is measured

• Dry goods are spoon-and-level. Spoon the ingredient into the cup until it mounds, then sweep the top flat with a straight edge. No tapping, no pressing.
• Brown sugar is firmly packed, because that is what every recipe that calls for it assumes.
• Liquids are measured by volume in a liquid measure, read at eye level, at room temperature.
• Butter assumes stick butter at about 80 percent milkfat, the US standard.

Rounding, and the tilde

Primary densities are published as whole grams. We do not publish decimal places on a cup measurement, because the honest error band on filling a cup by hand is several grams wide — a decimal point would be false precision. Derived numbers (tablespoon and teaspoon weights) carry one decimal below 10 g, because at that scale the decimal is real.

In the handling tables, a tilde (~) marks a working estimate rather than a published figure. Those numbers describe a real effect we can state directionally — a scooped cup of flour is heavier, a cup of sliced almonds is lighter — where the exact figure depends on brand, grind, or how hard the cup was packed. We would rather mark the uncertainty than invent a precise number.

What we will not publish

• A figure we cannot trace to a published source or derive arithmetically from one.
• Filler prose written to hit a word count. If we have nothing useful to say about an ingredient's storage or substitutions, that section does not appear on the page.
• Medical, nutritional, or food-safety advice beyond widely published guidance from named authorities, and never as a substitute for it.

Review cadence

Each of the 54 ingredient pages carries the date its content was last reviewed, shown in the byline at the top of the page and published in that page's dateModified structured data. The current dataset was published 2026-05-12 and the ingredient copy was last reviewed end-to-end on 2026-07-29. When a figure changes, the date changes with it.

Corrections

If a number here is wrong, we want to know, and we would rather hear it with a source than not hear it at all. Email hello@nathanmanagement.pro or use the contact form. Tell us the ingredient, the figure you think is wrong, and what you measured or which reference you are working from. Corrections are made to the underlying dataset, which updates the converter, the tables, and the structured data at once, and the page's review date is bumped.

Advertising and independence

The site is funded by display advertising, capped at two ad units per page. Ads are never styled to look like content and never appear inside the conversion tables. There are no affiliate links on this site, no sponsored ingredient pages, and no brand has ever paid to change a figure or be named in a recommendation. Where a brand is named — Diamond Crystal versus Morton salt, for instance — it is because the brands genuinely behave differently and the reader needs to know which one the recipe assumed.

Who is responsible

Ingredient Weight Converter is published by Nathan Management. Andrew Flores is responsible for what appears on it, including every figure in every table. More about the site and why it exists is on the about page.