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Ideal Race Weight Calculator

Target racing weight from lean mass and a realistic timeline to reach it.

Enter your values

ⓘ Live results

Results
Target race weight
70 kg (154.3 lb)
Weight to lose
5 kg
Lean mass to protect
63 kg
Weeks needed
13.3
Loss per week
0.38 kg
Daily calorie deficit
413 kcal
Minimum healthy weight
66.3 kg at 5% body fat

Working

  1. 1lean = 75 x (1 - 16%) = 63 kg
  2. 263 / (1 - 10%) = 70 kg

Quick answer

Race weight is set by lean mass, not by a height chart. Hold lean mass constant, choose a realistic racing body fat, and the target weight follows.

race weight = lean mass / (1 - target body fat)

How to use the Ideal Race Weight Calculator

  1. 1Enter your current weight and a body fat measurement you trust.
  2. 2Choose a racing body fat you have actually held before, not the lowest number you have read about.
  3. 3Use the weekly rate to time the cut so you arrive at race weight two weeks early, not on race morning.

Worked example

Using the values the calculator loads with:

Inputs

  • Current weight75 kg
  • Current body fat16 %
  • Target race body fat10 %
  • Weekly loss rate0.5 % of bodyweight

Results

  • Target race weight70 kg (154.3 lb)
  • Weight to lose5 kg
  • Lean mass to protect63 kg
  • Weeks needed13.3
  • Loss per week0.38 kg
  • Daily calorie deficit413 kcal
  • Minimum healthy weight66.3 kg at 5% body fat
  1. lean = 75 x (1 - 16%) = 63 kg
  2. 63 / (1 - 10%) = 70 kg

Frequently asked questions

How low should race body fat go?

Roughly 8 to 12% for male endurance athletes and 15 to 20% for female athletes. Going lower usually costs power, immunity and hormonal health.

Why lose only 0.5% of bodyweight per week?

Faster losses come substantially from lean mass and glycogen, which lowers power output — the opposite of what racing weight is for.

About this calculator

Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.