Carb Calculator
Find how many grams of carbohydrate to eat per day. Enter your details and your goal to see your daily calories and your carb target at the low end, the middle, and the high end of the recommended range.
How the carb calculator works
There is no single correct carb number. Health authorities set a range, and the right spot inside it is a personal choice. The calculator estimates your daily calories for your goal, then converts the recommended share of those calories into grams of carbohydrate.
The formula
Daily calories come from the Mifflin-St Jeor equation and your activity level, adjusted for your goal: minus 500 to lose weight, plus 400 to gain. The Acceptable Macronutrient Distribution Range set by the National Academies puts carbohydrate at 45 to 65 percent of calories, and each gram of carbohydrate supplies 4 calories. On 2,000 calories that works out to 225 to 325 grams a day. Results are rounded to the nearest 5 grams.
Choosing your spot in the range
Very active people and endurance athletes often do better toward the high end, because carbohydrate fuels hard training. If you prefer more protein or fat, or find fewer carbs easier to stick to, the low end works too. The Recommended Dietary Allowance of 130 grams a day is the amount set to cover the glucose the brain uses, so treat it as a floor unless you are following a supervised low-carb plan.
Frequently asked questions
How many carbs should I eat per day?
For most people the Acceptable Macronutrient Distribution Range puts carbohydrate at 45 to 65 percent of daily calories. On a 2,000-calorie diet that is about 225 to 325 grams a day, since each gram of carbohydrate supplies 4 calories. The calculator works out the range for your own calories.
How many carbs should I eat to lose weight?
There is no single carb number for weight loss. Fat loss comes from an overall calorie deficit, not from carbs specifically, so you can lose weight across a wide range of carb intakes. Many people do well toward the lower end of the 45 to 65 percent range, which leaves more room for protein.
Is 100 grams of carbs a day low carb?
Yes. 100 grams a day is below the bottom of the 45 to 65 percent range for most calorie levels, so it counts as a moderately low-carb intake. It also sits under the 130-gram Recommended Dietary Allowance, the reference set to cover the glucose the brain uses.
What is the minimum amount of carbs per day?
The Recommended Dietary Allowance for carbohydrate is 130 grams a day for adults, set to cover the amount of glucose the brain uses. Lower-carb diets go below that and suit some people for adherence, but they are a choice rather than a requirement for fat loss.
Do carbs make you gain weight?
Not by themselves. Weight gain comes from eating more calories than you burn, whatever the source. Carbohydrate quality matters more than the gram count: fiber-rich whole grains, fruit, vegetables, and legumes are easier to fit into a healthy diet than refined carbs and added sugars.