Your daily carbs, down to the gram.
Enter your daily calorie target and your protein and fat goals, and see exactly how many grams of carbohydrates fill the rest, along with the calories they supply, their share of your diet, and the fiber that should come with them.
Your daily targets
Your total daily calorie target.
Your daily protein target in grams.
Your daily fat target in grams.
Protein and carbs supply 4 kcal per gram, fat supplies 9. The calculator subtracts protein and fat calories from your target and converts what remains into carbohydrate grams. Results update as you type.
What your carb target means
Carbs by diet style at your calories
Carb thresholds at your calorie target
Carb share vs grams at your calories
Every row uses your daily calorie target. The highlighted row is the closest to your current carbohydrate share.
| Share of calories | Carbs | Carb calories | Diet style |
|---|
Carbohydrates, explained
Understanding Carbohydrates
Carbohydrates are your body's primary source of energy, providing 4 calories per gram. They are broken down into glucose, which fuels your brain, muscles, and organs. Carbs are classified as simple (sugars) or complex (starches and fiber), with complex carbs generally being the healthier choice for sustained energy.
How Many Carbs Do You Need?
The Dietary Guidelines recommend 45-65% of calories from carbohydrates. However, your needs depend on your goals: athletes may need 55-65% for performance, while those on low-carb diets may target 20-30%. This calculator determines your carb needs based on the calories remaining after protein and fat are accounted for.
Choosing Quality Carbohydrates
Focus on complex carbohydrates from whole grains, vegetables, fruits, and legumes. These provide fiber, vitamins, and minerals alongside energy. Limit refined carbs and added sugars from white bread, pastries, candy, and sugary drinks, which provide empty calories and cause blood sugar spikes.
Carbs and Exercise Performance
Carbohydrates are the preferred fuel source during moderate to high-intensity exercise. Depleted glycogen stores lead to fatigue and decreased performance. Athletes should consume carbs before, during (for events over 60 minutes), and after exercise to maintain energy and support recovery.
Common questions
Are carbs bad for you?
Carbohydrates are not inherently bad. Whole, unprocessed carbs from vegetables, fruits, whole grains, and legumes provide essential nutrients and fiber. The quality and quantity of carbs matter more than avoiding them entirely. Refined carbs and added sugars should be limited.
How does this calculator work?
This calculator subtracts the calories from your protein (4 cal/g) and fat (9 cal/g) targets from your total daily calories. The remaining calories are divided by 4 to determine your carbohydrate target in grams.
What if the calculator shows negative carbs?
If your protein and fat targets exceed your total calorie target, the remaining carbs will be negative or very low. This means your protein and fat targets are too high for your calorie goal, or your calorie target is too low. Adjust accordingly.
Should I eat carbs before bed?
Eating carbs before bed does not inherently cause weight gain. Total daily calorie intake matters more than timing. Some research suggests evening carbs may even improve sleep quality. However, avoiding large meals close to bedtime is generally good for digestion.
This calculator is an educational tool, not medical or dietary advice. Carbohydrate needs vary with activity, health conditions and medications, and people with diabetes, prediabetes, kidney disease or any condition affected by blood sugar should never change their carbohydrate intake without professional guidance. Talk to a doctor or registered dietitian before starting any diet, especially a very low-carb plan.