Just the CarbsGet it on Google Play

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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.

Unit on the label

The “carbohydrate” line on the label. Use the total, not sugars.

How much you’re eating, in g, to match the label.

Optional. You type the protein figure yourself.

Carbs

–g

Enter both values to see your carbs.

The working

Carbs per 100 × portion ÷ 100

Exact result
–
Shown, one decimal place
–
Whole grams
–

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

Example

51.5 × 30 ÷ 100

Exact15.45 g
Shown, one decimal15.5 g
Whole grams15 g

Rounding 15.5 again would give 16. Starting from 15.45 gives 15.

Reading the label

  1. Use the total carbohydrate line

    That’s the figure this calculator expects. It makes no fibre, sugar or net-carb adjustments.

  2. Match the unit to the label

    Label says per 100 g, weigh in grams. Label says per 100 ml, measure in millilitres.

  3. 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.

  4. 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.

See what the app does