How Many Calories Should Skinny Guys Eat to Bulk Up?

December 31, 2025 •

4 min read

A calorie surplus is essential for muscle gain, with many experts recommending an extra 300 to 500 calories per day to support growth. This guide provides a detailed approach to help skinny guys determine the optimal calorie intake for bulking up effectively.

Quick Summary

This article explores the science behind bulking for skinny individuals, including how to calculate daily calorie needs and create a strategic surplus. It covers macronutrient ratios, optimal food choices, and strategies for healthy weight gain.

Key Points

Calculate Your TDEE: Use a BMR formula and activity multiplier to find your maintenance calories before adding a surplus.
Start with a Moderate Surplus: Aim for 300-500 calories over your TDEE to maximize lean muscle gain and minimize fat.
Prioritize High-Quality Macronutrients: Maintain a balanced intake, focusing on adequate protein (1.6-2.2g/kg), moderate carbs (40-50%), and healthy fats (20-30%).
Choose Calorie-Dense Foods: Incorporate nuts, seeds, full-fat dairy, and healthy oils to increase calorie intake without feeling too full.
Utilize Liquid Calories: Bulking shakes are an easy and effective way to consume extra calories when a fast metabolism or small appetite makes eating difficult.
Track Your Progress: Weigh yourself weekly and adjust your calorie intake by 200-300 calories if your rate of gain is too slow or fast.
Pair with Resistance Training: Muscle growth is dependent on a combination of a calorie surplus and consistent, intense weightlifting to stimulate repair and growth.

Understanding Calorie Surplus for Muscle Growth

For skinny individuals, often referred to as 'hardgainers' or ectomorphs, consuming more calories than you burn is essential for bulking. Your body requires a consistent energy surplus to fuel muscle repair and growth, also known as muscle protein synthesis. Simply eating 'more' is often not enough, as a high metabolism can burn through excess energy quickly. A targeted and sustainable calorie surplus is essential to maximize lean muscle gain while minimizing unwanted fat storage.

Calculating Your Starting Calorie Target

The first step is to estimate your Total Daily Energy Expenditure (TDEE), which is the number of calories you burn each day. Online calculators or formulas can help determine this.

Estimate Basal Metabolic Rate (BMR): BMR is the energy your body uses at rest. A quick formula for men is: (10 x weight in kg) + (6.25 x height in cm) – (5 x age in years) + 5.
Apply your activity level: Multiply your BMR by an activity factor to get your TDEE.
- Sedentary (little to no exercise): BMR x 1.2
- Lightly active (1-3 days of exercise): BMR x 1.375
- Moderately active (3-5 days of exercise): BMR x 1.55
- Very active (6-7 days of exercise): BMR x 1.725
Add a surplus: Once you have your TDEE, add a moderate calorie surplus. For most skinny guys, a starting point of 300-500 extra calories per day is ideal for steady, lean gains. A larger surplus of 700-1000 can lead to faster weight gain, but also increases the risk of gaining excess body fat.

Macronutrient Breakdown for Ectomorphs

While the total calorie count is crucial, the ratio of macronutrients—protein, carbs, and fats—dictates how your body uses that energy. For bulking, a balanced approach is recommended to support muscle growth and provide energy for intense workouts.

Protein: This is the building block of muscle. Aim for 1.6–2.2 grams of protein per kilogram of body weight per day (or 0.7-1.0 grams per pound).
Carbohydrates: Your body's primary energy source. Carbs fuel your workouts and restore glycogen stores. Aim for 40-50% of your total daily calories from carbs.
Fats: These are essential for hormone production and overall health. Healthy fats should make up 20-30% of your daily calories.

Strategies to Consistently Eat More Calories

For those with smaller appetites, consuming enough calories can feel like a challenge. Here are some effective strategies to hit your targets without feeling uncomfortably full all the time:

Increase meal frequency: Try eating five to six smaller, nutrient-dense meals instead of three large meals throughout the day.
Prioritize calorie-dense foods: Choose foods that pack a lot of calories into a smaller volume. Examples include nuts, seeds, nut butters, avocados, and full-fat dairy.
Incorporate bulking shakes: Liquid calories are easier to consume in large quantities. A bulking shake with milk, oats, peanut butter, and protein powder can add hundreds of calories effortlessly.
Add healthy fats: Drizzle olive oil on salads, add cheese to your meals, or eat fattier cuts of meat like salmon.
Snack smartly: Replace low-calorie snacks with trail mix, dried fruit, or Greek yogurt to boost your intake.

Monitoring Your Progress

Consistent progress is your best indicator. Weigh yourself once a week at the same time to track your gains. A healthy rate of weight gain is typically 0.25–0.5% of your body weight per week. If you're not gaining weight, increase your daily calorie intake by 200-300 calories and monitor again. If you're gaining weight too quickly (and accumulating fat), reduce your surplus slightly.

Comparison of Bulking Strategies


Feature	Clean Bulk (Recommended)	Dirty Bulk (Not Recommended)
Calorie Surplus	Moderate (+300-500 calories)	Aggressive (+500-1000+ calories)
Food Quality	Focuses on whole, nutrient-dense foods	Includes highly processed, sugary, and high-fat junk foods
Fat Gain	Minimizes excess fat accumulation	Often results in significant, unwanted fat gain
Long-Term Health	Supports overall health and well-being	Poses higher risks to metabolic and cardiovascular health
Sustainability	Easier to maintain and adjust over time	Often leads to a cycle of bulking and aggressive cutting

Sample Meal Plan for a 3,000+ Calorie Bulk

This is a starting template for a moderately active skinny guy aiming for a 3,000+ calorie diet. Adjust portion sizes and food choices to meet your specific TDEE and preferences.

Meal 1: High-Calorie Breakfast

Oatmeal (1 cup dry) cooked with milk (1 cup)
1 scoop whey protein powder
1 tbsp peanut butter
1 banana, sliced
Handful of almonds

Meal 2: Mid-Morning Snack

Full-fat Greek yogurt (1 cup)
Mixed berries (1/2 cup)
A handful of walnuts

Meal 3: Balanced Lunch

Grilled chicken breast (6 oz)
Brown rice or quinoa (1.5 cups cooked)
Mixed vegetables (broccoli, spinach)
Drizzle of olive oil

Meal 4: Pre-Workout Meal/Snack

Protein shake made with milk
Sweet potato (1 medium)
Optional: A piece of dried fruit

Meal 5: Post-Workout Meal

Salmon fillet (6 oz)
Roasted potatoes (1-2 medium)
Asparagus, roasted with garlic

Meal 6: Evening Snack/Before Bed

Cottage cheese (1 cup)
Nut butter (1 tbsp)
Small side of nuts or seeds

Conclusion: The Final Word on Caloric Intake

To effectively bulk up, skinny guys must focus on a consistent caloric surplus of 300-500 calories above their maintenance level, fueling their bodies with a balanced diet rich in protein, carbs, and healthy fats. Calculating your TDEE is the starting point, but regular monitoring of weight gain is essential for making precise adjustments. Prioritizing nutrient-dense, high-calorie foods and incorporating bulking shakes can help overcome a fast metabolism and smaller appetite. For best results, pair this targeted nutritional plan with consistent resistance training to ensure those extra calories are converted into lean muscle mass, not excess fat. For more detailed nutritional guidance, consider visiting the Journal of the International Society of Sports Nutrition for research-backed insights on optimizing diet for muscle growth.

For more information on bulking and nutrition, visit [https://www.healthline.com/nutrition/clean-bulk].

Frequently Asked Questions

For skinny guys, a good macronutrient ratio for bulking is typically around 40-50% carbohydrates, 30-35% protein, and 20-30% fats to provide energy and support muscle growth.

Hardgainers can overcome a fast metabolism by eating frequently throughout the day and prioritizing calorie-dense foods like nuts, dried fruit, and full-fat dairy, along with incorporating bulking shakes to increase overall caloric intake.

While consuming junk food will increase calories, a 'dirty bulk' is not recommended. It often leads to significant fat gain and offers poor nutritional value, negatively impacting overall health and energy levels for workouts.

Aim for a slow and steady weight gain of about 0.5 to 1 pound (0.25-0.5 kg) per week to maximize muscle gain while minimizing fat accumulation.

Supplements are not necessary but can be helpful. A diet focused on whole foods is key, but some may use whey protein or mass gainer supplements to help hit their daily calorie and protein targets more easily.

If you struggle to eat enough, focus on calorie-dense foods and use liquid calories, like bulking shakes, to make up the difference. Spread your meals out into more frequent, smaller portions to make digestion easier.

Skinny guys should focus on resistance training with an emphasis on compound exercises like squats, deadlifts, and bench presses, which work multiple muscle groups and are highly effective for stimulating muscle growth.