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Protein & Macro Calculator for Runners

Work out your daily calories, protein, carbohydrate and fat as a runner, from your body size and how much you run — based on current sports-nutrition guidelines.

About you and your training

Estimates are a starting point — adjust based on your energy, recovery and weight trend.
Daily macros

How much protein do runners need?

Running breaks down muscle protein, and your body needs dietary protein to repair it and to build the enzymes, tendons and red blood cells that endurance training depends on. The 2016 joint position statement from the American College of Sports Medicine, the Academy of Nutrition and Dietetics and Dietitians of Canada recommends 1.2–2.0 g of protein per kg of body weight per day for athletes — well above the roughly 0.8 g/kg guideline for the general population.

Body weight1.2 g/kg1.4 g/kg1.6 g/kg1.8 g/kg2.0 g/kg
50 kg (110 lb)60 g70 g80 g90 g100 g
55 kg (121 lb)66 g77 g88 g99 g110 g
60 kg (132 lb)72 g84 g96 g108 g120 g
65 kg (143 lb)78 g91 g104 g117 g130 g
70 kg (154 lb)84 g98 g112 g126 g140 g
75 kg (165 lb)90 g105 g120 g135 g150 g
80 kg (176 lb)96 g112 g128 g144 g160 g
85 kg (187 lb)102 g119 g136 g153 g170 g
90 kg (198 lb)108 g126 g144 g162 g180 g
100 kg (220 lb)120 g140 g160 g180 g200 g

Where you sit in the range depends on your goals: around 1.4–1.6 g/kg suits most endurance runners, while the upper end (1.8–2.0 g/kg) helps during very heavy training, when combining running with strength work, or when eating in a calorie deficit to lose fat while preserving muscle.

Spreading protein through the day

Research on muscle protein synthesis suggests spreading intake across the day works better than one large serving. A practical target is about 0.3 g/kg per meal (roughly 20–30 g for most adults) across four meals or snacks, including one within a couple of hours after hard sessions.

How many carbohydrates do runners need?

Carbohydrate is the main fuel for hard running, and needs rise steeply with training load:

Training loadCarbohydrate70 kg runner
Light (low intensity or skill-based)3–5 g/kg/day210–350 g
Moderate (~1 hour a day)5–7 g/kg/day350–490 g
High (1–3 hours a day, moderate–high intensity)6–10 g/kg/day420–700 g
Very high (4–5+ hours a day)8–12 g/kg/day560–840 g

Fat makes up the remainder of your energy needs, typically 20–35 % of calories. Very low-fat diets are not recommended for athletes.

Example: 70 kg runner, 40 km per week
Calories from each macronutrient at roughly 2,880 kcal per day. Your exact numbers from the calculator depend on your height, age and daily activity.

How the calorie estimate works

  1. Resting energy is estimated with the Mifflin–St Jeor equation from your weight, height, age and sex.
  2. Daily life multiplies that by a lifestyle factor (1.2–1.5) for activity outside running.
  3. Running adds about 1 kcal per kg of body weight per km, spread over the week.
  4. Your goal applies a modest adjustment — a 15 % deficit for gradual fat loss or a 10 % surplus for muscle gain.

Under-fuelling is a real risk. Consistently eating too little for your training — known as low energy availability or RED-S — can harm bones, hormones, immunity and performance. If you are losing weight quickly, feel constantly tired, get frequent injuries or (for women) notice changes to your menstrual cycle, speak to a doctor or registered sports dietitian.

Planning a long race? Use the race fueling calculator for carbs during the event, and the running calories calculator for the energy cost of individual runs.

  • Thomas DT, Erdman KA, Burke LM (2016). Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and Athletic Performance. J Acad Nutr Diet 116(3):501–528.
  • Jäger R et al. (2017). International Society of Sports Nutrition position stand: protein and exercise. J Int Soc Sports Nutr 14:20.
  • Mifflin MD et al. (1990). A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr 51(2):241–247.

Last reviewed: September 2026 · Health disclaimer

FAQ

Runner Macros questions

Sports-nutrition guidelines recommend about 1.2–2.0 g of protein per kg of body weight per day for athletes. Many endurance runners do well around 1.4–1.6 g/kg, with more during heavy training blocks or when trying to lose fat while keeping muscle.

Carbohydrate needs scale with training: about 3–5 g/kg/day for light training, 5–7 g/kg for about an hour a day, 6–10 g/kg for 1–3 hours a day, and 8–12 g/kg for very high volumes.

Fat usually makes up the rest of your energy needs — typically 20–35 % of calories. Very low fat intakes are not recommended because fat supports hormone health and the absorption of fat-soluble vitamins.

The calculator estimates resting energy with the Mifflin–St Jeor equation, adds a lifestyle factor for daily activity, and adds the energy cost of your weekly running (about 1 kcal per kg per km). Treat the number as a starting point and adjust based on your weight trend and energy levels.