Cornstarch
Metric Cup to Gram
US Cup (236ml)
127.8g
Metric Cup (250ml)
135.0g
A US cup (236.59ml) of cornstarch weighs 128g, while a metric cup (250ml) weighs 135g. That's a 5.7% difference - make sure you know which cup size your recipe uses!
Cornstarch — Quick Reference
Common metric cup to gram conversions
| Metric Cup | Gram |
|---|---|
| ¼ cup | 34g |
| ⅓ cup | 45g |
| ½ cup | 68g |
| ⅔ cup | 90g |
| ¾ cup | 101g |
| 1 cup | 135g |
| 1½ cups | 203g |
| 2 cups | 270g |
Based on cornstarch density of 0.54 g/ml (spooned method). Source: USDA FoodData Central.
Understanding Cornstarch Conversions
The Math Behind This Conversion
To convert 1 metric cup of cornstarch to gram, we use the density of cornstarch (0.54 g/ml). A metric cup contains 250ml, so 1 metric cup equals 250ml. Multiplying by the density: 250ml × 0.54 g/ml = 135g.
US vs Metric Cups: Why It Matters
When converting cornstarch, the cup size matters significantly. A US cup (236.6ml) of cornstarch weighs 128g, while a metric cup (250ml) weighs 135g—a difference of 7g (6%). If you're following a recipe from a different country, using the wrong cup size could affect your results. American recipes use US cups, while recipes from Australia, UK, and most other countries use metric cups.
Measurement Tip
For best results when measuring cornstarch, use a kitchen scale. The density of 0.54 g/ml is based on standard measurement conditions, but actual results may vary based on how the ingredient is handled and stored.
About Our Data
The density value of 0.54 g/ml for cornstarch is from the USDA FoodData Central database (ID: 169698). This measurement was taken with cornstarch spooned into the measuring cup and leveled.