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Calorie Surplus Calculator

To gain weight or build muscle, you need to eat more calories than you burn. This calorie surplus calculator gives you daily calories for a lean bulk or standard bulk, plus protein targets and how fast you can expect to gain.

A clean bulk typically requires a daily surplus of 250 to 500 kcal above your Total Daily Energy Expenditure (TDEE). This supports muscle protein synthesis while keeping fat gain minimal, producing roughly 0.25 to 0.5 kg (0.5 to 1 lb) of gain per week.

Units
kg
years
cm

Target Bulking Intake

+500 kcal Surplus
3,150kcal / day

Standard bulk: Ideal for intermediate trainees seeking consistent strength and muscle mass gains.

Maintenance TDEE

2,650 kcal

Daily baseline calories

Expected Rate of Gain

~0.5 kg / wk

Lean muscle & mass gain

Suggested Bulking Macronutrient Split

MacronutrientDaily TargetCaloriesShareRationale
Protein130 g520 kcal17%1.8 g/kg bodyweight to maximize muscle protein synthesis
Carbohydrates461 g1842 kcal58%Fuel for progressive overload training sessions and recovery
Dietary Fat88 g788 kcal25%25% of energy intake to optimize anabolic hormone production

Evidence-based guidelines (ISSN & Helms et al.) recommend 1.6–2.2 g/kg protein during caloric surplus to maximize lean muscle mass accretion.

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Clinical Equations

WHO, CDC, ACSM & Mifflin-St Jeor

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How to use Calorie Surplus Calculator

  1. 1Enter your sex, age, height, current body weight, and exercise activity level.
  2. 2Select your bulking target: Lean Bulk (+250 kcal), Standard (+500 kcal), or Hardgainer (+700 kcal).
  3. 3Review your daily bulking calorie budget, expected rate of gain, and targeted macronutrients.

Lean bulk vs aggressive bulk

A controlled lean bulk (+250 kcal/day) maximizes the ratio of muscle to fat gained. Muscle synthesis has an upper physiological ceiling; eating in a 1,000+ kcal surplus does not build muscle faster, but accelerates fat storage.

Beginners with high insulin sensitivity can thrive on a standard +500 kcal surplus, while advanced lifters benefit from a smaller +200 to +300 kcal surplus to avoid unnecessary cutting phases.

Macronutrient targets for bulking

Protein should be set at 1.6 to 2.2 g per kilogram of body weight. Dietary fat should supply roughly 20% to 30% of total calories to sustain testosterone and hormone health. The remainder is filled with carbohydrates to fuel progressive resistance training.

Frequently Asked Questions

How big should my calorie surplus be?

250 to 500 kcal/day for most people. Beginners can use the higher end; experienced lifters the lower end.

How fast should I gain weight on a bulk?

About 0.25 to 0.5% of body weight per week keeps fat gain low.

How much protein do I need when bulking?

1.6 to 2.2 g per kg of body weight per day.

Related Calculators

TDEE Calculator

Estimate your Total Daily Energy Expenditure and discover your true maintenance calories.

Calorie Calculator

Calculate your daily calorie needs for weight loss, maintenance, or muscle gain.

Macro Calculator

Calculate your daily macronutrients (protein, carbs, and fat) for weight loss or muscle building.

Protein Calculator

Calculate your daily protein requirements based on body weight, fitness goals, and training intensity.

Carbohydrate Intake Calculator

Calculate your daily carbohydrate requirements by percentage of calories or athlete training load.

Scientific Sources & Evidence

Last reviewed: September 2026
All calculations adhere to our peer-reviewed verification protocols. Read our Editorial Policy & Scientific Review Standards.