Calculate your optimal calorie deficit and macros to shred fat efficiently.
Male
Female
Required for Basal Metabolic Rate (BMR) calculation.
Please enter a valid age between 18 and 100.
Please enter a valid height (100-250 cm).
Please enter a valid weight.
Goal weight must be less than current weight for cutting.
Sedentary (Office job, little exercise)
Lightly Active (1-3 days/week exercise)
Moderately Active (3-5 days/week exercise)
Very Active (6-7 days/week hard exercise)
Extra Active (Physical job + training)
Multiplies your BMR to find Total Daily Energy Expenditure (TDEE).
How this is calculated: We estimate your BMR using the Mifflin-St Jeor equation, multiply by your activity level to find your maintenance calories (TDEE), and then subtract a caloric deficit based on your desired weight loss pace (approx. 7700 kcal deficit per 1kg of fat loss).
Macronutrient Breakdown (Cutting Strategy)
Prioritizing protein to spare muscle mass during the deficit.
Nutrient
Grams/Day
Calories
% of Total
Projected Weight Loss Timeline
Blue Line: Weight Projection | Dashed Line: Goal Weight
What is a Cutting Weight Calculator?
A cutting weight calculator is a specialized financial-grade tool designed for athletes, bodybuilders, and fitness enthusiasts who need to reduce body fat while maintaining lean muscle mass. Unlike generic weight loss tools, a cutting calculator accounts for the specific metabolic demands of maintaining muscle tissue during a caloric deficit.
This tool is ideal for individuals preparing for a physique competition, athletes needing to make a specific weight class, or anyone looking to improve their body composition ("get shredded") for health or aesthetic reasons. It helps eliminate the guesswork by providing precise caloric targets and macronutrient ratios tailored to your unique physiology.
Common misconceptions about cutting include the idea that you must starve yourself or cut out entire food groups. In reality, a successful cut relies on a controlled, mathematical energy deficit combined with adequate protein intake to preserve muscle tissue.
Cutting Weight Calculator Formula and Mathematical Explanation
The core logic behind this cutting weight calculator relies on the principle of thermodynamics: Energy In vs. Energy Out. However, calculating the exact numbers requires a multi-step formula.
Step 1: Basal Metabolic Rate (BMR)
We use the Mifflin-St Jeor Equation, widely considered the most accurate formula for estimating BMR in clinical settings:
BMR is multiplied by an Activity Factor to determine TDEE (maintenance calories):
Variable
Meaning
Typical Range
BMR
Basal Metabolic Rate (Coma calories)
1,200 – 2,200 kcal
AF
Activity Factor
1.2 (Sedentary) to 1.9 (Athlete)
Deficit
Calories removed daily
250 – 1,000 kcal
Step 3: The Deficit Calculation
To lose weight, you must consume fewer calories than your TDEE. The standard scientific approximation is that a deficit of roughly 7,700 kcal is required to lose 1 kg of body fat.
Scenario: Mark is a 30-year-old male, 180cm tall, weighing 90kg. He lifts weights 4 times a week (Moderately Active) and wants to cut to 85kg for summer.
TDEE Calculation: His maintenance is approximately 2,900 kcal.
Result: Mark needs to eat 2,350 kcal daily. He will reach his goal in approximately 10 weeks.
Example 2: The Mini-Cut
Scenario: Sarah is a 25-year-old female, 165cm tall, weighing 65kg. She is sedentary at work but trains hard (Lightly Active). She wants a quick trim to 63kg.
TDEE Calculation: Maintenance is roughly 1,800 kcal.
Goal: Lose 0.5kg per week (Aggressive for her size).
Deficit Required: 550 kcal/day.
Result: Sarah needs 1,250 kcal daily. Because this is low, she might opt for a slower pace (0.25kg/week) to keep calories higher (around 1,500 kcal).
How to Use This Cutting Weight Calculator
Enter Your Stats: Input accurate gender, age, height, and current weight. Honesty is critical for accurate BMR calculations.
Select Activity Level: Be realistic. Most people overestimate their activity. If you have a desk job and lift weights 3x a week, "Lightly Active" or "Moderately Active" is often safer than "Very Active".
Set Your Pace: Choose a weight loss rate. We recommend 0.5kg (approx 1lb) per week as a sustainable balance between speed and muscle preservation.
Review Macros: The results table breaks down your calories into Protein, Fats, and Carbs. Stick to the protein target to maintain muscle mass while cutting weight.
Key Factors That Affect Cutting Weight Results
Using a cutting weight calculator gives you a roadmap, but execution involves several variables:
Non-Exercise Activity Thermogenesis (NEAT): This is the energy burned by fidgeting, walking, and standing. When you cut calories, your body subconsciously reduces NEAT, lowering your TDEE. You may need to manually increase step counts to offset this.
Metabolic Adaptation: Over time, your body becomes more efficient, burning fewer calories for the same work. You may need to recalculate your numbers every 4-6 weeks as you lose weight.
Macronutrient Composition: Protein has a higher thermic effect of food (TEF) than fats or carbs, meaning you burn more calories digesting it. High protein intake supports the deficit.
Sleep Quality: Poor sleep increases ghrelin (hunger hormone) and decreases insulin sensitivity, making a cut significantly harder to adhere to.
Water Weight: High sodium intake or carbohydrate refeeds can cause temporary water retention, masking fat loss on the scale.
Cheat Meals: One un-tracked "cheat day" can easily erase the calorie deficit created during the previous 6 days. Consistency is mathematically essential.
Frequently Asked Questions (FAQ)
How fast should I cut weight?
A generally safe rate is 0.5% to 1% of your body weight per week. For most people, this is 0.5kg to 1kg. Faster rates increase the risk of muscle loss and metabolic slowdown.
Why has my weight loss stalled?
As you lose weight, your BMR decreases (a smaller body requires less energy). You likely need to recalculate your numbers using your new, lower body weight.
Should I eat back my exercise calories?
Generally, no. The "Activity Level" multiplier in the calculator already accounts for your exercise. Adding them back in usually leads to double-counting and eating at maintenance instead of a deficit.
Can I build muscle while cutting?
It is possible, especially for beginners or those with high body fat percentage, but it is difficult. The primary goal of a cut is usually retention of muscle, not growth.
What if the calculator says I need fewer than 1,200 calories?
It is generally not recommended to drop below 1,200 kcal for women or 1,500 kcal for men without medical supervision, as micronutrient deficiencies become likely. Increase activity instead of lowering food further.
Does nutrient timing matter?
Total daily intake is the most important factor. However, consuming protein evenly throughout the day and carbohydrates around your workout can improve performance and satiety.
How accurate is this cutting weight calculator?
It is an estimate based on population averages. Your personal metabolism may vary by 10-15%. Use the result as a starting point and adjust based on scale weight trends over 2-3 weeks.
Do I need supplements to cut weight?
No. A caloric deficit is the only requirement. Supplements like caffeine or protein powder can help with energy and convenience, but they do not directly burn fat significantly.
Related Tools and Resources
TDEE Calculator – Determine your exact daily maintenance energy needs before starting a cut.
Macro Calculator – A deeper dive into optimizing your protein, fat, and carb ratios.