Body Metrics

What body fat percentage changes

Supplying body composition adds a third formula that uses lean mass, and moves the protein target.

Daily energy need

3,017–3,202kcal

The range is the answer. The formulas disagree by 107 kcal (5.9%) before the very active multiplier of 1.725 is applied.

BMI

26.1

Overweight

By WHO Asian-population cutoffs: Increased risk

Healthy range for this height: 56.7–76.3 kg

Protein

55–83g/day

General health

Computed on lean body mass (68.8 kg). The RDA floor is 0.8 g/kg; many bodies recommend more for older adults.

Every formula, side by side

  • Mifflin-St Jeor1,749 kcal

    The most widely recommended of the three for general use.

  • Harris-Benedict (revised)1,830 kcal

    Older, and tends to read higher than Mifflin-St Jeor.

  • Katch-McArdle1,856 kcal

    Uses lean mass rather than total weight, so it is the better estimate when body composition is known — especially at either extreme of muscularity.

Height

175.0 cm · 5' 9"

Weight

80.0 kg · 176.4 lb (12st 8lb)

What to read before using any of this

  • Read this

    The formulas disagree by 107 kcal (5.9%)

    Resting expenditure comes out between 1749 and 1856 kcal depending on which standard equation you use, and both are fitted to population averages rather than to you. After the activity factor the plausible range is 3017-3202 kcal. Any calculator that reports a single number to the calorie is implying precision that does not exist.

    What to do: Treat the range as the answer. Pick a point inside it, hold it for a few weeks, and adjust based on what actually happens to your weight — measured response beats any formula.

  • Note

    The activity multiplier is the largest source of error

    The multipliers run from 1.2 to 1.9, so the choice between two adjacent bands moves the estimate by roughly 306 kcal — more than the disagreement between the formulas. Most people overestimate their own activity level.

    What to do: If you are between two bands, take the lower one and adjust upward from evidence.

  • Note

    Not medical advice

    These are population-level estimates from formulas fitted to population averages. They are not medical advice and know nothing about your health, medication, pregnancy, or history. BMI in particular is not a measure of health. Talk to a clinician or a registered dietitian before acting on any of it.

Run your own numbers

Use the form on the home page, or call the API or MCP server. This page is available as markdown.

Related examples

Not medical advice, and not a substitute for talking to a clinician or a dietitian. Produces population-level estimates from formulas fitted to population averages; it knows nothing about an individual's health, medication, pregnancy, or history. Does not diagnose anything, and BMI in particular is not a measure of health.