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RepFitLAB

LAB·03Mifflin-St Jeor · adaptive

Weight planner

Tell us where you are and where you want to be. The plan recalculates every week as your body changes, so the timeline is honest.

  • Free
  • Private
  • No sign-up needed

Your stats

Sex

yrs
cm
kg
kg
%Makes the maths more precise

Activity

Pace

Daily target

—

Enter your height and weight to start, then add tape measurements for precision.

How it works

  1. Your starting point

    Height, weight, age and how much you move give your maintenance calories.

  2. A pace you can keep

    Choose a percentage of body weight per week. We never go below a safe minimum.

  3. A plan that adapts

    Targets step down as you change, so the timeline is realistic from day one.

Sources

  • Mifflin-St Jeor equation · American Journal of Clinical Nutrition, 1990
  • Katch-McArdle equation · Resting energy from lean body mass

RepFit Lab gives estimates to guide your training, not medical advice. If you have a medical condition, are pregnant or have a history of disordered eating, talk to a doctor before changing how you eat or train.