Corn Syrup:
Grams to Cups
One cup of corn syrup weighs 340 grams. This thick glucose syrup is essential in candy making and confectionery baking, where it prevents sugar crystallization and produces a smooth, glossy texture in caramels, marshmallows, and pecan pie filling.
Convert Corn Syrup
1 cup = 340 grams
= — grams
= — cups
Quick reference
Measurement Table
| Cups | Grams | Ounces |
|---|---|---|
| ⅛ cup | 43 g | 1.52 oz |
| ¼ cup | 85 g | 3.00 oz |
| ⅓ cup | 113 g | 3.99 oz |
| ½ cup | 170 g | 6.00 oz |
| ⅔ cup | 227 g | 8.01 oz |
| ¾ cup | 255 g | 8.99 oz |
| 1 cup | 340 g | 11.99 oz |
| 1¼ cups | 425 g | 14.99 oz |
| 1½ cups | 510 g | 17.99 oz |
| 2 cups | 680 g | 23.99 oz |
| 3 cups | 1020 g | 35.98 oz |
About Corn Syrup
Corn syrup's primary function in baking and candy making is as an invert sugar — it interferes with sucrose crystallization, keeping caramels, fudge, and icings smooth and pliable. Without it, reheated sugar solutions recrystallize into a grainy texture. Just a small proportion (1–2 tablespoons per cup of sugar) is enough to inhibit crystallization significantly.
Light corn syrup has a neutral sweetness and is used in recipes where color must remain light — pecan pie, peanut brittle, marshmallows, and white fondant. Dark corn syrup has added molasses and a stronger flavor, used where a robust, caramel-like sweetness is desired. Both varieties weigh 340 g per cup.
At 340 g per cup, corn syrup is among the densest ingredients in baking. Accurate measurement matters most in candy making, where ratios between sugar and syrup determine whether a candy reaches the soft-ball, firm-ball, or hard-crack stage. Small errors compound quickly at high temperatures.
For measuring, spray the inside of your measuring cup lightly with cooking spray before filling. Corn syrup slides out cleanly, ensuring your full 340 g goes into the recipe rather than being left behind on the cup walls.
Tips for measuring Corn Syrup
- Spray the measuring cup with cooking oil first for clean, complete release.
- Light corn syrup for color-sensitive recipes; dark for rich, molasses-flavored results.
- Even small amounts (1–2 tbsp) prevent sugar crystallization in candy.
- Warm the bottle slightly in warm water if the syrup is too thick to pour.
Common mistakes
- Leaving syrup behind on the measuring cup — spray or oil it first.
- Confusing light and dark corn syrup — they have noticeably different flavors.
- Measuring by eye in candy making — a few grams off affects the candy stage.
Frequently Asked Questions
- How many grams in a cup of Corn Syrup?
- 1 cup of Corn Syrup weighs 340 grams. This is the standard measurement used in most American recipes.
- How many cups is 340 grams of Corn Syrup?
- 340 grams of Corn Syrup equals exactly 1 cup. For partial amounts, use the converter above or the measurement table.
- Is 340 g per cup accurate for all brands?
- 340 g/cup is the widely accepted standard. Minor brand-to-brand variation exists (±5–10%), but for most baking purposes this figure is reliable.