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Weight Loss Calorie Calculator

Use the Weight Loss Calorie Calculator to estimate calorie deficits, fat reduction targets, and healthy weight goals.

Weight Loss Calorie Calculator TOOL

Estimate daily calorie targets for weight loss instantly using age,
gender, weight, height, activity level, and desired deficit goals.

The Weight Loss Calorie Calculator determines how many calories a person should consume each day to reduce body weight in a controlled and measurable way. It calculates daily maintenance energy needs, subtracts a chosen calorie deficit, and estimates weekly fat loss based on the energy gap created.

The calculator transforms body measurements, age, biological sex, and activity level into a daily calorie recommendation for weight reduction.

It produces three core outputs:

  • Maintenance Calories — calories required to maintain current body weight
  • Weight Loss Calorie Target — calories to consume for fat reduction
  • Estimated Weekly Weight Loss — predicted body weight reduction per week

1. Calculator Inputs

The calculator uses six required inputs.

Gender

Gender affects resting energy expenditure because average muscle mass and metabolic demand differ.

Options:

  • Male
  • Female

Age

Age influences metabolism because resting calorie expenditure generally decreases over time.

Measured in years.


Weight

Current body mass in kilograms.

Weight = Body mass in kilograms

Height

Height is entered in centimeters and converted internally when needed.

Height in meters = Height in cm 100

Activity Level

This estimates daily movement and exercise.

Activity LevelMultiplier
Sedentary1.2
Lightly Active1.375
Moderately Active1.55
Very Active1.725
Extremely Active1.9

Daily Calorie Deficit

The selected deficit is subtracted from maintenance calories.

Choices:

  • 250 Calories
  • 500 Calories
  • 750 Calories
  • 1000 Calories

A larger deficit produces faster weight loss but may increase fatigue and hunger.


2. Step One: Basal Metabolic Rate

The calculator first estimates Basal Metabolic Rate (BMR).

This is the amount of energy required to sustain life at rest.

For males:

BMR = 10 × Weight + 6.25 × Height 5 × Age + 5

For females:

BMR = 10 × Weight + 6.25 × Height 5 × Age 161
Basal Metabolic Rate Components Weight Height Age Gender

The combined result estimates resting calorie expenditure.


3. Step Two: Maintenance Calories

Maintenance calories represent total daily energy expenditure.

Maintenance Calories = BMR × Activity Multiplier

This reflects calories burned through:

  • Basic survival
  • Walking
  • Exercise
  • Digestion
  • Daily movement

4. Step Three: Weight Loss Target

The chosen deficit is subtracted.

Weight Loss Calories = Maintenance Calories Deficit

This is the recommended daily calorie intake.


5. Step Four: Weekly Weight Loss Estimate

Approximately:

7700 calories = 1 kilogram of body fat

Weekly fat loss:

Weekly Loss = Daily Deficit × 7 7700

Typical results:

  • 250 deficit → ~0.23 kg/week
  • 500 deficit → ~0.45 kg/week
  • 750 deficit → ~0.68 kg/week
  • 1000 deficit → ~0.91 kg/week

Calorie Deficit vs Weekly Loss 250 500 750 1000

Higher deficits increase expected weekly loss.


6. Practice Exercise

A user enters:

  • Gender: Male
  • Age: 30
  • Weight: 82 kg
  • Height: 178 cm
  • Activity: Moderately Active
  • Deficit: 500 Calories

Step 1: BMR

10 × 82 + 6.25 × 178 5 × 30 + 5

Result:

1787.5 calories


Step 2: Maintenance

1787.5 × 1.55

Result:

2770 calories


Step 3: Weight Loss Target

2770 500

Result:

2270 calories/day


Step 4: Weekly Loss

500 7700 × 7

Result:

0.45 kg per week


Final Interpretation

The calculator predicts:

  • Maintenance Calories: 2770
  • Weight Loss Target: 2270
  • Weekly Weight Loss: 0.45 kg

This indicates a sustainable reduction pace, allowing measurable fat loss while preserving energy for training and recovery.

The Weight Loss Calorie Calculator converts physical characteristics and lifestyle activity into a structured nutritional target, allowing controlled, predictable progress toward lower body weight.