What is Carb Calculator?
Carbohydrate is the body's preferred fuel for high-intensity exercise and the most flexible of the three macros — you can eat a lot or a little and still be healthy, depending on activity and preference. This calculator converts a share of your calorie target into grams of carbohydrate. Because carbs are the flexible macro, most people set protein and fat first and let carbohydrate absorb the remainder, which naturally means more carbs on training days and fewer on rest days. General guidance suggests 45–65% of calories from carbohydrate for most people; endurance athletes often exceed that, while low-carb approaches sit under about 130 g a day.
Common Uses for Carb Calculator
- Set a daily carb target for training
- See how much carbohydrate a calorie budget allows
- Plan higher-carb training days and lower-carb rest days
- Convert percentage-based plans into grams
Frequently Asked Questions
How many carbs do I need a day?
For general health, 45–65% of calories (about 225–325 g on a 2,000 kcal diet). Endurance athletes may need 6–10 g/kg on heavy training days. Low-carb diets sit below about 130 g.
Are carbs bad for weight loss?
No. Fat loss depends on a calorie deficit, not carbohydrate per se. Low-carb diets often work because they reduce appetite and calories, not because carbs are uniquely fattening.
What are good carb sources?
Whole grains, oats, potatoes, beans, lentils, fruit and vegetables provide carbohydrate with fibre, micronutrients and slower digestion. Refined sources are fine in moderation but easier to over-consume.
More Macro & Nutrition Calculators
Macro Calculator
Protein, carbohydrate and fat targets in grams from a daily calorie target and a chosen split.
Macro Calculator for Weight Loss
Fat-loss macros with a high protein share to protect muscle while in a deficit.
Protein Calculator
Daily protein target in grams based on body weight and goal.
Keto Macro Calculator
Keto macros: around 70% fat, 25% protein and under 5% carbohydrate.