Calorie Deficit Calculator

Calculate your daily calorie target for sustainable weight loss

Formula

TDEE = BMR × Activity Factor; Deficit = (Current - Goal) × 7700 ÷ Days; Target = TDEE - Daily Deficit

BMR uses Mifflin-St Jeor. TDEE multiplies BMR by activity factor. 1 kg fat ≈ 7700 kcal. Safety floor prevents dangerous deficits.

How to Calculate Manually

1
Calculate BMR using Mifflin-St Jeor equation
2
Multiply by activity factor for TDEE
3
Determine total weight to lose
4
Calculate total deficit needed (kg × 7700)
5
Divide by days to get daily deficit
6
Subtract from TDEE for target calories
7
Apply safety floor (1200F/1500M)
8
Recalculate expected weight loss

Reference Table

Deficit/Day	Weekly Loss	Monthly Loss	Sustainability
250 kcal	0.23 kg	0.9 kg	Very Easy
500 kcal	0.45 kg	1.8 kg	Easy
750 kcal	0.68 kg	2.7 kg	Moderate
1000 kcal	0.91 kg	3.6 kg	Hard
1250 kcal	1.13 kg	4.5 kg	Very Hard

Calorie Deficit Calculator: How to Lose Weight Safely and Sustainably

Weight loss comes down to energy balance: consume fewer calories than you burn. But the devil is in the details. This guide covers calculating your deficit, setting realistic goals, and avoiding common pitfalls...

Frequently Asked Questions

What is a safe calorie deficit? 500-750 calories/day for 1-1.5 lbs/week loss. Never go below 1200 calories (women) or 1500 (men) without medical supervision. Larger deficits risk muscle loss and metabolic slowdown.: 500-750 calories/day for 1-1.5 lbs/week loss. Never go below 1200 calories (women) or 1500 (men) without medical supervision. Larger deficits risk muscle loss and metabolic slowdown.
How accurate is TDEE? TDEE estimates are ±10-15%. Use as starting point, then adjust based on actual weight change over 2-3 weeks. Track consistently.: TDEE estimates are ±10-15%. Use as starting point, then adjust based on actual weight change over 2-3 weeks. Track consistently.
Should I eat back exercise calories? Most calculators already include activity. If you add extra exercise, you can eat back 50% of estimated burn (trackers overestimate). Better to set activity level honestly.: Most calculators already include activity. If you add extra exercise, you can eat back 50% of estimated burn (trackers overestimate). Better to set activity level honestly.

Calculator

Formula

Formula

How to Calculate Manually

Reference Table

Calorie Deficit Calculator: How to Lose Weight Safely and Sustainably

Frequently Asked Questions

Related Calculators

BMI Calculator

BMR Calculator

Body Fat Percentage Calculator

Daily Water Intake Calculator

More Health Calculators

Absolute Neutrophil Count (ANC) Calculator

Anion Gap Calculator

Apgar Score Calculator

BMI Calculator

BMR Calculator

Body Fat Percentage Calculator