Carb calculator: carbs and calories in your portion
To find the carbohydrate in your portion, multiply the label carbohydrate per serving by the number of servings you ate. For a per-100 g label, multiply by the grams you ate and divide by 100. For example, 22 g per serving and 1.5 servings is 33 g.
How it works
- Per serving: value per serving × servings eaten.
- Per 100 g: value per 100 g × grams eaten ÷ 100.
Read how to read a food label for carbs for where to find each number.
Information, not medical advice. Talk to your care team about your own targets and treatment. Never use a converter or a diary entry to work out an insulin or medicine dose.
Sources
- American Diabetes Association: How to read nutrition labels
- NIDDK: Diet, eating and physical activity
Frequently asked questions
Should I subtract fibre?
Some care plans subtract fibre from total carbohydrate and others do not. This calculator uses the total carbohydrate you enter. Ask your dietitian or care team which method to follow.
Can I use this to calculate an insulin dose?
No. This calculator only multiplies label values for a diary. It never suggests or calculates medicine or insulin doses.
How accurate is it?
It is exact arithmetic on the numbers you enter. Labels round their values, so the result is close, not exact.
Keep reading
Reading labels for carbs
How to find carbohydrates on a nutrition label: serving size, total carbohydrate, fibre and added sugars, with a simple way to work out your portion.
Food and carbsThe plate method
How to build a balanced plate with the plate method: half non-starchy vegetables, a quarter protein and a quarter high-fibre carbohydrate.
Food and carbsGlycemic index
What the glycemic index (GI) measures, how foods are rated low, medium or high, and why portion size and the rest of the meal still matter.