Quick examples
Gender
Mifflin–St Jeor uses different constants for men and women.
Basal Metabolic Rate
1,452kcal/day
Calories your body burns at complete rest
Mifflin–St Jeor
adult formula
Total Daily Energy Expenditure
2,251kcal/day
Maintenance burn at “Moderately active” activity
BMR
1,452
kcal at rest
TDEE
2,251
maintenance
Activity burn
799
above BMR · ×1.55
Activity
Moderately active
3–5 workouts / week
Cut target
1,801
~0.4–0.75 kg/week deficit band
Surplus target
2,551
gentle lean-gain band
TDEE by activity level
Same BMR × each standard activity factor. Your selection is highlighted.
Sedentary
×1.2 · Desk job, little exercise
1,742
Lightly active
×1.375 · 1–3 workouts / week
1,997
Moderately activeYou
×1.55 · 3–5 workouts / week
2,251
Very active
×1.725 · Daily exercise or physical job
2,505
Athlete
×1.9 · Intense training 2× / day
2,759
BMR 1,452 · TDEE 2,251 kcal — take action
Turn these numbers into meals & workouts
- ✓ Calorie & macro targets from your metabolism
- ✓ Cuisine-based Week 1 meal plan
- ✓ Gym or home workouts matched to your level
- ✓ Print or save your plan as PDF
Mifflin–St Jeor 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 (1.2–1.9)
Widely used for adult calorie estimates. Results are approximations — muscle mass, hormones, illness, and medications can shift true needs. Not medical advice.
BMR Calculator — Quick Reference
The BMR Calculator is an online tool that calculate your Basal Metabolic Rate (BMR) with Mifflin–St Jeor, then see TDEE by activity level — metric or imperial, with cut and surplus calorie bands. Everything for the BMR Calculator is on this page: the interactive calculator, the formula, a worked example, step-by-step guidance, and frequently asked questions — no other pages required.
At a glance
- Main inputs
- Weight (kg or lb)
- Height (cm or ft/in)
- Age and gender
- Activity level (sedentary through athlete)
- Main outputs
- BMR (kcal/day at rest) using Mifflin–St Jeor
- TDEE (maintenance calories) for your activity level
- Activity burn above BMR
- Suggested cut and surplus calorie bands
Direct answers
What is the BMR Calculator?
The BMR Calculator is an online tool that calculate your Basal Metabolic Rate (BMR) with Mifflin–St Jeor, then see TDEE by activity level — metric or imperial, with cut and surplus calorie bands.
What formula does the BMR Calculator use?
We use the Mifflin–St Jeor equation — currently preferred for most adults. Men: 10×weight(kg) + 6.25×height(cm) − 5×age + 5. Women: 10×weight(kg) + 6.25×height(cm) − 5×age − 161. The result is rounded to whole kcal/day.
How does the BMR Calculator work?
Enter age, gender, weight, and height (metric or imperial), then pick an activity level. We compute Mifflin–St Jeor BMR, TDEE for each activity factor, activity calories above rest, and gentle cut/surplus bands — with a link to build a full diet and workout plan.
Formula Used
The equation below is what this calculator applies. Variable definitions follow when symbols are used.
Equation
Men: BMR = 10×kg + 6.25×cm − 5×age + 5
Additional rules
- Women: BMR = 10×kg + 6.25×cm − 5×age − 161
- TDEE = BMR × activity factor
Worked Example: 70 kg woman, 170 cm, age 30, moderately active — BMR & TDEE?
Sample inputs and the results this calculator produces for the scenario below.
Inputs
- Weight
- 70 kg
- Height
- 170 cm
- Age / sex
- 30 · female
- Activity
- Moderately active (×1.55)
Results
- BMR
- 1,452 kcal/day
- TDEE
- 2,251 kcal/day
BMR = 10×70 + 6.25×170 − 5×30 − 161 = 1,451.5 ≈ 1,452 kcal. Moderately active TDEE = 1,452 × 1.55 ≈ 2,251 kcal — a practical maintenance starting point.
How BMR Calculator Works
Enter age, gender, weight, and height (metric or imperial), then pick an activity level. We compute Mifflin–St Jeor BMR, TDEE for each activity factor, activity calories above rest, and gentle cut/surplus bands — with a link to build a full diet and workout plan.
What to enter
Use the calculator above to set your amounts, rates, and tenure. Results update as you move sliders or type values — switch currency if you are planning in USD, INR, or another supported unit.
Step-by-step
- Choose metric or imperial units and enter age, gender, weight, and height.
- Pick the activity level that best matches your week.
- Read BMR, TDEE, and the cut/surplus targets.
- Use the Health Plan to turn these calories into meals and workouts.
BMR — Frequently Asked Questions
Each question is answered directly below. Expand any item for the full response.
How is BMR calculated?
We use the Mifflin–St Jeor equation — currently preferred for most adults. Men: 10×weight(kg) + 6.25×height(cm) − 5×age + 5. Women: 10×weight(kg) + 6.25×height(cm) − 5×age − 161. The result is rounded to whole kcal/day.
What is the difference between BMR and TDEE?
BMR is resting burn only. TDEE multiplies BMR by an activity factor (about 1.2 if sedentary up to ~1.9 for athletes) to estimate total daily calories including movement and exercise.
Should I cut below my BMR?
Sustained eating far below BMR is usually not advisable without clinical supervision. For weight loss, a modest deficit from TDEE (often ~400–750 kcal) is a more common starting approach than dropping under BMR.
Does muscle raise BMR?
Yes — more lean mass generally raises resting energy expenditure. Equations based only on weight, height, age, and sex cannot see muscle, so muscular athletes may burn more than the estimate and under-muscled people somewhat less.
Is Mifflin–St Jeor accurate?
It is one of the most validated formulas for estimating adult BMR in the general population and usually outperforms older Harris–Benedict versions. Individual results still vary with muscle mass, thyroid function, and genetics.
Should I eat at my BMR?
No — BMR is what you burn at complete rest. Most people need closer to TDEE (BMR × activity) to maintain weight. A large chronic deficit below BMR is hard to sustain and not a good default without clinical supervision.
How do I pick an activity factor?
Be honest about weekly movement. Desk job with little exercise ≈ sedentary (1.2). Gym 3–5 days ≈ moderate (1.55). Daily hard training or a physical job ≈ very active / athlete. Overestimating activity is the most common calorie-tracking mistake.
Disclaimer
- This calculator gives you an estimate only. It is not a promise of exact results.
- This is general information, not personal financial, tax, or legal advice.
- You are responsible for your own decisions. Talk to a qualified professional when it matters.
- BMI, BMR/TDEE, and weight guidance are screening estimates only — not a medical diagnosis. Consult a healthcare professional for personal advice.
Related Calculators
BMI Calculator
Calculate your Body Mass Index (BMI) with metric or imperial units, see WHO category, healthy weight range, and personalised insights.
Age Calculator
Calculate your exact age in years, months, and days from your date of birth — plus total days lived, next birthday countdown, live seconds counter, and life milestones.
Age Difference Calculator
Find the exact age difference between two people — years, months, days, and total days between their birth dates.
FLAMES Calculator
Play the classic FLAMES love game — enter two names to reveal Friends, Lovers, Affectionate, Marriage, Enemies, or Siblings.