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Onboarding calculation

Calorie Target Methodology

How onboarding calculates standard calories, lean-mass-adjusted maintenance, and the final target calories.

Status: Used to generate the daily calorie target stored after onboarding.
Last updated: June 15, 2026

Inputs and outputs

Inputs

  • Age
  • Gender
  • Height
  • Weight
  • Activity level
  • Goal
  • Resolved body fat percentage
  • Seasonal calorie setting

Outputs

  • Standard calories
  • Lean-mass maintenance calories
  • Final target calories
  • Seasonal calorie adjustment when enabled

Formula

Mifflin male BMR = 10 * weight_kg + 6.25 * height_cm - 5 * age + 5
Mifflin female BMR = 10 * weight_kg + 6.25 * height_cm - 5 * age - 161
activity_multiplier = sedentary 1.2, light 1.375, moderate 1.55, active 1.725, veryactive 1.9
standard_calories = BMR * activity_multiplier * goal_multiplier
standard goal_multiplier = lose 0.9, maintain 1.0, gain 1.1
lean_mass_rmr = 370 + (21.6 * lean_mass_kg)
maintenance = lean_mass_rmr * activity_multiplier + seasonal_adjustment
final_target = round(maintenance * true_needs_goal_multiplier)
true_needs_goal_multiplier = lose 0.85, maintain 1.0, gain 1.1

Calculation steps

  1. Calculate a conventional Mifflin-St Jeor estimate as a standard reference.
  2. Calculate the main Unflame target from lean mass using a Cunningham/Katch-McArdle-style resting metabolic estimate.
  3. Apply the selected activity multiplier.
  4. Apply a goal multiplier: stronger deficit for loss, maintenance for maintain, surplus for gain.
  5. Apply seasonal calories only when enabled by the user.

Guardrails

  • The target is an estimate for planning, not a metabolic test.
  • Actual body-weight trend, hunger, training, symptoms, and clinical context should override the estimate over time.
  • Seasonal calorie adjustment is stored separately so it can be disabled.

Sources

These formulas describe how Unflame estimates onboarding targets. They are planning estimates and should be reviewed against real-world trends, user preference, symptoms, and professional guidance where relevant.