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Carbohydrate Calculator

Estimate your daily carbohydrate target from BMR, TDEE and your chosen carb approach.

Related tools

All Nutrition tools →
Alcohol Calorie CalculatorAdd up the calories of a drinking session from a library of beers, wines, spirits and cocktails, with a custom-drink option.Breastfeeding Calorie CalculatorExtra daily calories while breastfeeding — about +500 kcal exclusive, with a gradual weight-loss option.Carb-to-Insulin Ratio CalculatorEstimate a starting carb ratio from your total daily dose using the 400/450/500/550 rule, with an optional mealtime bolus.Intermittent Fasting CalculatorPlan your fasting and eating windows (16:8, 18:6, OMAD…) from your last meal time.Net Carbs CalculatorCompute net carbs from total carbs, fiber and sugar alcohols, per serving and per day.Calories per meal calculatorSplit your daily calorie target evenly across your meals.Daily sugar intake calculatorFind your WHO free-sugar limit from your daily calorie intake.Fiber intake calculatorFind your recommended daily fiber from sex and age (IOM).

Carbohydrate Calculator is free to use as often as you like, directly from this page. It sits under Nutrition in our catalogue, alongside Alcohol Calorie Calculator and Breastfeeding Calorie Calculator.

How to use it

  1. Open the tool — no signup or install needed.
  2. Enter your input or adjust the available options.
  3. Get your result instantly, then copy or download it.

Frequently asked questions

What does Carbohydrate Calculator do?

Estimate your daily carbohydrate target from BMR, TDEE and your chosen carb approach.

When would I actually use this?

Planning meals against a target, checking whether a habit covers the recommended intake, and translating a label into what it means for the day.

What is the most common mistake?

Treating a daily target as a daily requirement. Reference intakes are population averages over time; a day above or below one means nothing on its own.

Is there a tool for the next step?

Breastfeeding Calorie Calculator is the closest one after this: Extra daily calories while breastfeeding — about +500 kcal exclusive, with a gradual weight-loss option.

What else is worth having open alongside it?

Carb-to-Insulin Ratio Calculator and Intermittent Fasting Calculator — they come up in the same task often enough to be worth a second tab.

Where do the figures come from?

Reference intakes come from public health bodies (EFSA in Europe, the NIH and USDA in the United States) and differ between them. They describe populations, not you, and are not medical advice.

Further reading

All guides →
ExplainerHow Much Carbohydrate Do You Actually Need?There is a small hard answer — the brain's glucose demand, published as 130 g a day — and a very large soft one. Above the minimum, carbohydrate need scales with training volume in grams per kilogram, not with a percentage.Comparison16/8, 5:2 or Alternate Day: The Fasting Protocols ComparedFive protocols side by side, what each demands, and the uncomfortable finding from the controlled trials: matched for calories, fasting loses about the same weight as simply eating less.How-toHow to Calculate Keto Macros (Without Starting From the Percentages)Set carbs as a fixed gram figure, protein by body weight, and let fat fill what is left. The famous 75 percent fat is an output of that calculation, not an input — and it drops on its own in a deficit.ExplainerThe Carbohydrate-to-Insulin Ratio, and the Rule That Estimates ItThe ratio says how many grams of carbohydrate one unit of insulin covers, and the usual starting estimate is 500 divided by the total daily dose. Here is where that number comes from, how sharply it moves across daily doses, why a 450 version exists, and the three things it quietly assumes.ExplainerWhat Breastfeeding Actually Costs in Energy — and Why the Published Number Is Smaller Than the MilkMilk production has a computable cost: volume times energy density divided by the efficiency of conversion. Do the sum and you get about 675 kcal a day, not the 500 that gets quoted. Here is the derivation, why the published increment is deliberately lower, how much the real spread is between mothers, what the water requirement actually rests on, and why cutting calories while feeding is a clinical question.ExplainerThe Calories in a Drink Are Mostly the AlcoholEthanol carries 7 kcal per gram and the arithmetic is exact: volume × ABV × 0.789 × 7. A dry spirit is almost pure alcohol calories; a liqueur is nearly half sugar. Here is the derivation, the table, and the metabolic caveat stated without overclaiming.