Nouriq
Free nutrition tool
Glycemic load calculator
Estimate how a food’s glycemic index and the available carbohydrate in your serving combine. Use the result as one piece of context—not a prediction of your personal glucose response.
Calculate GL for one serving
How the calculation works
GL = GI × (total carbohydrate − dietary fiber) ÷ 100
This tool estimates available carbohydrate by subtracting dietary fiber from total carbohydrate. That convention works for standard U.S. Nutrition Facts labels, where total carbohydrate includes dietary fiber. If your source already reports available or digestible carbohydrate, enter that amount as total carbohydrate and enter zero fiber.
| Estimated GL | Common band |
|---|---|
| 10 or less | Low |
| 11–19 | Medium |
| 20 or more | High |
Worked example
A serving with GI 60, 24 grams of total carbohydrate, and 4 grams of fiber contains an estimated 20 grams of available carbohydrate.
60 × (24 − 4) ÷ 100 = GL 12
That result falls in the commonly used medium range. A different serving size changes the GL even when the GI stays the same.
What this estimate cannot tell you
- GI values vary by food variety, ripeness, processing, preparation, and test method.
- Mixed meals and individual physiology can produce a different glucose response.
- Food labels round nutrient amounts, so the output is not laboratory precision.
- This calculator must not be used for medication or insulin dosing.
Method sources
- Harvard T.H. Chan School of Public Health: Glycemic Load — formula and common bands.
- U.S. FDA: How to Understand and Use the Nutrition Facts Label — serving size, total carbohydrate, and dietary fiber.
- International tables of GI and GL values 2021 — standardized GI values and methodology.