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Carb calculator for your portion.
Label says per serving? See how to convert it.
Type the carbs per 100 from the label, then how much you’re having. The answer appears as you type, with the sum underneath.
Carbs
–g
Enter both values to see your carbs.
The working
Carbs per 100 × portion ÷ 100
- Exact result
- –
- Shown, one decimal place
- –
- Whole grams
- –
Protein, from the figure you typed
Protein per 100 × portion ÷ 100
- Exact result
- –
- Shown, one decimal place
- –
Calculated from the values you entered. Check them against the packaging.
Rounding
One decimal on top, whole grams beneath.
The calculator keeps the exact result and rounds only for display, halves going up. Whole grams are rounded from the exact figure, not from the decimal you see.
Why it matters
Example51.5 × 30 ÷ 100
| Exact | 15.45 g |
|---|---|
| Shown, one decimal | 15.5 g |
| Whole grams | 15 g |
Rounding 15.5 again would give 16. Starting from 15.45 gives 15.
Reading the label
Use the total carbohydrate line
That’s the figure this calculator expects. It makes no fibre, sugar or net-carb adjustments.
Match the unit to the label
Label says per 100 g, weigh in grams. Label says per 100 ml, measure in millilitres.
Weigh the food as the label describes it
If the label is for dry pasta, use the dry weight. A cooked weight needs a cooked value.
Label only gives per serving?
Convert it first: carbs per serving × 100 ÷ serving size in grams.Per 100 g vs per serving walks through it.
Limits: up to 100 per 100 g, or 200 per 100 ml, and a portion up to 100,000. Commas work as decimal points.
When you’re doing this a lot
The app looks up the carbs. You type the portion.
Just the Carbs for Android scans the barcode or nutrition label and does this sum for you. No account, no ads.
The app can show protein too, if you switch it on.
