Body composition
Female Athlete Formula Suite
Female forms of the common formulas: FFMI, Mifflin-St Jeor BMR, Gulati max heart rate and BMI-based body fat, with the caveats for your life stage.
Result
Your FFMI against the rough reference
22 kg/m² is a rough reference for natural women, not a measured ceiling.
Notes and caveats
- The FFMI reference of 22 is a rough guide: Kouri's 1995 natural ceiling of about 25 was measured in men, and no comparable study exists for women.
- Body fat is estimated from BMI and age (Deurenberg 1991), so FFMI inherits that estimate's error, often several points for lean or muscular women. A measured value is better.
- VO2max here is the average for untrained women of your age, not a measure of your fitness; a field test gives your own.
- Resting metabolism runs slightly higher in the luteal phase than the follicular phase, so treat BMR as a cycle midpoint.
Related calculators
- Body composition Body Fat Percentage Calculator
Estimate body fat percentage using the U.S. Navy circumference method.
- Nutrition TDEE Calculator
Estimate your daily energy expenditure with Mifflin-St Jeor + activity factors.
- Nutrition Macro Calculator
Convert calorie targets into protein, carbs, and fat grams for your goal.
- Planning Calorie Deficit Calculator
Estimate required daily calorie deficit for a target timeline and bodyweight change.
Articles
- 7 min read Female Athlete Formula Suite: A 30-Year-Old in Regular Cycle
Female athlete formulas for 65 kg, 168 cm, 24% body fat, regular cycle. The luteal-versus-follicular caloric drift and where male equations fail.
- 7 min read FFMI for the Intermediate Female Lifter: A 60kg/165cm/22% Walkthrough
FFMI for a 60kg, 165cm, 22% body-fat female intermediate lifter: adjusted 18.14 walkthrough, percentile context, and why the Kouri 25 cap was male-only.
Use it from an agent or code
Any agent can run this calculator by URL: put the inputs in the query string and get JSON back, with the inputs that used defaults and a line to cite (add format=md for markdown). MCP clients reach it through https://aifithub.io/mcp.
In code, import the same module; it runs where you import it, with no request or key.
import { compute } from "https://aifithub.io/engines/female-athlete-formula-suite.js";Input and output contract, TypeScript types and the guide for agents.