How We Calculate These Conversions

Short version: convert with confidence for everyday cooking, but weigh with a scale when a recipe needs to be exact.

Where the numbers come from

Cooking measurements mix two different things: volume (cups, tablespoons, millilitres) and weight (grams, ounces). To convert between them you need each ingredient's density — how much a given volume weighs.

• Volume ↔ volume (e.g. cups → ml) and weight ↔ weight (e.g. grams → ounces) are exact, fixed conversions. 1 US cup = 236.588 ml; 1 ounce = 28.3495 g.
• Volume ↔ weight (e.g. cups of flour → grams) depends on the ingredient. We use a representative grams-per-cup value for each one.

Our reference sources

Per-ingredient weights are cross-referenced against widely used, authoritative charts and, for liquids, derived directly from physical density:

• King Arthur Baking — Ingredient Weight Chart (a baking-industry standard).
• USDA FoodData Central (US food composition database).
• Physical density for water and water-based liquids (1 cup of water ≈ 237 g).

Why your result can differ

Volume measurement is inherently imprecise. The same cup of flour can vary by 20–30% depending on whether it's scooped, spooned, sifted or packed — plus brand and humidity. That's why our values are labelled approximate, and why serious bakers weigh ingredients. If you want one upgrade that fixes this forever, it's a digital kitchen scale.

Found a value that looks off?

These charts are maintained and refined over time. The goal is to be genuinely useful and honest about precision — not to pretend cup measurements are exact when they aren't.