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Free calculator
Weight cut calculator
Your weight, your class, your weigh-in date. Get the weekly pace, a safety verdict, and the daily calorie targets — worked out by the same engine the Fighter Cut app uses.
How the calculator works
It does four things, in order, and they are the same four the app does when it builds a camp plan.
1. It estimates your maintenance calories. Resting energy comes from the Mifflin-St Jeor equation, the standard used by most clinical dietitians, then it is multiplied by an activity factor. This is an estimate with an error of a few hundred calories either way. The app corrects it from your real weigh-ins after two or three weeks; a web form cannot.
2. It splits the loss into diet and water. A fight-week water loss of up to 3% of body weight is assumed and taken off the top. Everything else has to come off as body mass, through diet, before fight week starts.
3. It spreads the diet loss across the weeks you have. Weeks are counted back from the weigh-in. The final week is fight week and carries no diet loss; the week before it is a taper at half pace. Every other day of runway counts, including a short first week.
4. It caps the deficit and judges the pace. No day is ever planned more than 750 kcal under maintenance, which bounds planned diet loss to roughly 0.68 kg (1.5 lb) a week. The required pace is then graded:
| Weekly diet loss | Verdict |
|---|---|
| 1.5% of body weight or less | Safe |
| 1.5% to 2% | Caution |
| Over 2% | Unsafe |
| Cannot be reached at the 750 kcal cap | Not reachable, with the shortfall shown |
The calculator will not plan an intake below 1,500 kcal a day for men or 1,200 for women, and it will not tell you how to dehydrate. If the answer is "not reachable", the honest options are a later bout or a heavier class — that verdict is the most useful thing it can give you.
What it cannot tell you
A single calculation assumes your maintenance estimate is right and your weight moves in a straight line. Neither is true. Water, glycogen and gut content move the scale by a kilogram or more day to day, so a fighter who checks against a plan once a week will panic early and relax late. The pattern that matters is the trend over seven to fourteen days, set against the plan week by week — see reading a bodyweight trend in camp and how much weight you can cut before a fight.
It also knows nothing about your commission. Same-day weigh-ins, hydration testing and wrestling certification all change what is allowed; read missing weight in MMA and, for wrestlers, use the wrestling weight certification calculator.
Questions fighters ask
How much weight can I safely cut per week?
This calculator treats up to 1.5% of body weight a week as a safe diet pace and 1.5% to 2% as caution. Above 2% it flags the cut as unsafe. The daily deficit is also capped at 750 kcal, which limits planned diet loss to about 0.68 kg (1.5 lb) a week.
Does the calculator include the water cut?
It sizes one — up to 3% of body weight in fight week — so the diet target is realistic. It does not tell you how to do it. Acute dehydration belongs under a physician or registered dietitian and inside your commission’s rules.
Why does it say my cut is not reachable?
Because even at the maximum 750 kcal daily deficit, the weeks you have cannot remove the diet portion of the loss. It shows the shortfall. A later date or a heavier class are the options that do not risk your health.
How accurate is the maintenance calorie estimate?
It uses the Mifflin-St Jeor equation and an activity multiplier, which can be off by a few hundred calories. The Fighter Cut app recalculates maintenance from your real weigh-ins and food log after a few weeks.
Is this the same maths as the Fighter Cut app?
Yes. The page runs the app’s own plan engine, compiled for the web, so the verdict here and in the app are the same computation for the same inputs.
Does it work for wrestling, boxing, BJJ and Muay Thai?
Yes — the pace and calorie logic apply to any weigh-in. Wrestlers should also check their certified minimum weight, which the wrestling certification calculator works out.
Get the week-by-week plan
This page gives you one verdict. Fighter Cut turns it into a plan for every week to the scale, logs what you eat against it, and re-reads your trend as your weight moves. Free to track, works offline, and your data stays on your phone.
Get the iPhone appUse it in your browser