Calorie Deficit Calculator
Uses the standard resting-calorie equation for BMR, multiplies by activity to get TDEE, then suggests targets for a moderate calorie deficit.
| Age | years |
| Sex | |
| Height | cm |
| Weight | kg |
| Activity level | |
| Goal |
Result
Your result will appear here.
How it works
First calculate BMR (calories burned at rest) with a standard resting-calorie equation, multiply by an activity factor for TDEE (total daily energy expenditure), then subtract a deficit for weight loss.
Formula
Men: BMR = 10×weight(kg) + 6.25×height(cm) − 5×age + 5
Women: BMR = 10×weight(kg) + 6.25×height(cm) − 5×age − 161
TDEE = BMR × activity factor
Target = TDEE − deficit
Worked example
A 30-year-old male, 175 cm, 80 kg, moderately active: BMR ~1739, TDEE ~2695, at 500 kcal deficit target ~2195 kcal/day.
Assumptions
Estimates only. Factors like body composition, NEAT, hormones and medications affect needs. Very low intakes need care.
Reading the result
Start conservatively, track for 2-3 weeks and adjust. Hydration, sleep and strength training help preserve lean mass during a deficit.
For general information only. Not a substitute for professional medical/nutritional advice.
How to use the Calorie Deficit Calculator
It takes a few seconds, and every figure is calculated in your browser.
- Enter your age.
- Select your sex.
- Enter your height.
- Enter your weight.
- Pick your activity level.
- Pick your goal.
- Press Calculate — the result appears in the dark panel beside the form.
- Use Copy, CSV, Share or Print under the result if you want to keep it.
Calorie Deficit Calculator — frequently asked questions
What formula does the Calorie Deficit Calculator use?
Men: BMR = 10×weight(kg) + 6.25×height(cm) − 5×age + 5 Women: BMR = 10×weight(kg) + 6.25×height(cm) − 5×age − 161 TDEE = BMR × activity factor Target = TDEE − deficit
How does the Calorie Deficit Calculator work?
First calculate BMR (calories burned at rest) with a standard resting-calorie equation, multiply by an activity factor for TDEE (total daily energy expenditure), then subtract a deficit for weight loss.
What assumptions and limitations should I know about?
Estimates only. Factors like body composition, NEAT, hormones and medications affect needs. Very low intakes need care.
Can you walk through a worked example?
A 30-year-old male, 175 cm, 80 kg, moderately active: BMR ~1739, TDEE ~2695, at 500 kcal deficit target ~2195 kcal/day.
Last updated 10 November 2026 · Formula, worked example and assumptions are documented above, and every result is calculated in your browser.