Glycemic load calculator
Glycemic load (GL) = glycemic index (GI) × grams of available carbohydrate in a serving ÷ 100. A GL of 10 or less is low, 11–19 is medium and 20 or more is high. For example, a food with a GI of 50 in a serving with 30 g of carbs has a GL of 15 (medium).
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Glycemic load calculator
The glycemic load formula
GL = GI × available carbohydrate per serving (g) ÷ 100
GI must be on the glucose scale, where pure glucose is 100. Some older tables use white bread as the reference instead; to convert those, multiply by 0.7 (70/100), as the international GI tables do. Don't know your food's GI? Find it in our glycemic index food library.
We round GL to one decimal and rate the rounded value. The published bands are whole numbers, so a GL between 10 and 11 (for example 10.5) counts as medium.
Low, medium and high GI and GL
| Rating | Glycemic index | Glycemic load per serving |
|---|---|---|
| Low | 55 or less | 10 or less |
| Medium | 56–69 | 11–19 |
| High | 70 or more | 20 or more |
Glycemic load examples
The same GI gives a very different glycemic load depending on how many carbs are in the portion.
| GI | Available carbs | Glycemic load | Rating |
|---|---|---|---|
| 40 (low) | 20 g | 8.0 | Low |
| 55 (low) | 30 g | 16.5 | Medium |
| 70 (high) | 10 g | 7.0 | Low |
| 70 (high) | 15 g | 10.5 | Medium |
| 70 (high) | 50 g | 35.0 | High |
| 90 (high) | 10 g | 9.0 | Low |
What your result means
Glycemic load describes one serving. A low-GL choice (10 or less) is expected to raise blood sugar less than a high-GL one (20 or more). Because GL scales with portion size, halving a serving halves its GL, which is often the easiest way to bring a high-GL food down. For a whole meal, add up the GL of each part.
GI and GL are averages from small groups of people and can vary between brands and preparation methods, so treat them as a guide rather than an exact prediction for your own body.
Frequently asked questions
What is the difference between glycemic index and glycemic load?
Glycemic index (GI) ranks how much a food's carbohydrate raises blood sugar compared with pure glucose, which scores 100. Glycemic load (GL) also accounts for how much carbohydrate is in the serving you actually eat, so a high-GI food can still have a low GL in a small portion.
What is a good glycemic load?
Per serving, a glycemic load of 10 or less is considered low, 11 to 19 medium, and 20 or more high, according to the Harvard T.H. Chan School of Public Health.
Should I use total carbs or net carbs?
Use available carbohydrate, the carbohydrate your body digests and absorbs; that is how glycemic load is defined in the international GI tables. On US nutrition labels, total carbohydrate includes fiber, so subtracting dietary fiber gives a closer estimate.
Where can I find a food's glycemic index?
Look it up in our glycemic index food library, or in the international GI tables compiled by University of Sydney researchers. GI can vary between brands and cooking or manufacturing methods, so use the closest match you can find.
Does glycemic load predict my own blood sugar response?
Only roughly. GI values are averages measured in small groups of people, so your own response can differ. Tracking how you feel and respond after meals shows your personal pattern.
Sources
- Atkinson FS, Foster-Powell K, Brand-Miller JC. International tables of glycemic index and glycemic load values: 2008. Diabetes Care. 2008;31(12):2281–2283.
- Atkinson FS, Brand-Miller JC, Foster-Powell K, Buyken AE, Goletzke J. International tables of glycemic index and glycemic load values 2021: a systematic review. Am J Clin Nutr. 2021;114(5):1625–1632.
- Harvard T.H. Chan School of Public Health, The Nutrition Source. Carbohydrates and blood sugar.
- University of Sydney, Glycemic Index Research and GI News. About glycemic index.