BMR & TDEE Calculator — How to Calculate Daily Calories
Estimate basal metabolic rate (BMR) with Mifflin-St Jeor, Harris-Benedict, or Katch-McArdle, then multiply by an activity factor for TDEE. Example: male, 70 kg, 175 cm, age 30, Mifflin, activity 1.55 → BMR ≈ 1648.75 and TDEE ≈ 2555.56 kcal/day. Runs in your browser; educational only — not medical advice.
How it works
Enter sex, weight, height, and age. Pick a BMR equation (Mifflin by default). For Katch-McArdle, also enter body-fat percent. Choose an activity factor to get TDEE ≈ BMR × factor. Deficit or surplus ideas stay on this page as FAQ — not separate calorie tools.
Formula and assumptions
Mifflin (male): 10w + 6.25h − 5a + 5; female uses −161. Harris-Benedict revised and Katch-McArdle (370 + 21.6 × lean mass) are selectable. Assumptions:
- Inputs are adult educational estimates; equations differ and are not diagnoses.
- Activity factors are rough multipliers, not wearable measurements.
- Harris and Katch share this URL — no separate calculator pages.
- Not medical, nutrition, or weight-loss advice.
Example
Example: male, 70 kg, 175 cm, age 30, Mifflin-St Jeor, activity 1.55 → BMR ≈ 1648.75 kcal/day and TDEE ≈ 2555.56 kcal/day.
When to use it
- Classroom: compare Mifflin vs Harris on the same body stats.
- Rough maintenance calorie sketch before talking to a clinician (illustration only).
- See how activity factors change TDEE without a separate calorie URL.
Frequently asked questions
What is BMR vs TDEE?
BMR is estimated resting burn; TDEE multiplies BMR by an activity factor for a rough daily total.
Which equation should I pick?
Mifflin-St Jeor is a common default. Harris is revised classic; Katch needs body-fat % and uses lean mass.
Can I plan a calorie deficit here?
This page explains the idea in FAQ only. It does not prescribe diets or medical plans.
Is this medical advice?
No. Numbers are educational illustrations only and are not medical or nutrition advice.
What if body-fat % is missing for Katch?
Katch-McArdle needs a body-fat percent between 0 and 100. Switch to Mifflin if you do not have it.
Important notice
BMR and TDEE results are educational estimates only and are not medical, diagnostic, or nutrition advice. Individual needs vary; seek qualified care for health decisions.
References: NCBI Bookshelf metabolism education materials; NHLBI educational BMI/weight resources; standard Mifflin-St Jeor / Harris-Benedict / Katch-McArdle formulas.
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Questions or feedback
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