How big a weight cut is safe?

Cuts up to about three percent of bodyweight are generally manageable; three to five percent requires care; over five percent is aggressive and can impair health and performance. This tool flags larger cuts and assumes the final portion is acute water loss, not fat.

What is the difference between a gradual and water cut?

A gradual cut removes real bodyweight over days or weeks through a modest calorie and carbohydrate deficit. A water cut is the final acute phase — manipulating fluid, sodium, and food volume in the last day or two — and must be rehydrated after weigh-in.

How does this split the cut?

The tool reserves roughly the final two percent of bodyweight for acute water and gut manipulation in the last day, then spreads the remaining cut as gradual daily loss across the days before. This keeps day-to-day deficits realistic and recoverable.

Is rapid weight cutting dangerous?

It can be. Aggressive dehydration carries real risks including heat illness, kidney strain, and reduced performance, and has caused serious harm in combat sports. Always cut under qualified supervision and never push beyond what your timeline safely allows.

What should I do after weigh-in?

Rehydrate and refuel systematically — fluids with electrolytes and easily-digested carbohydrates — to restore the water and glycogen lost in the cut. The amount you can recover before competing is a key reason not to cut more than necessary.

Competition Weight & Weight Cut Calculator

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Making weight for competition is a planning problem with real safety limits. This calculator takes your walk-around weight, target class, and timeline and lays out a day-by-day cut, separating gradual loss from the acute final-day water cut — and flags when the cut is too large to do safely.

How it works

The tool computes the total cut, expresses it as a percentage of bodyweight, and splits it into gradual and acute phases:

total cut   = current weight − target weight
cut percent = total cut / current weight × 100
acute (water/gut) = min(total cut, 2% of bodyweight)   ← final 1–2 days
gradual     = total cut − acute   ← spread across remaining days
per-day gradual = gradual / (days − 1)
safety: > 5% bodyweight → flagged as aggressive

Reserving the final couple of percent for water manipulation keeps the daily gradual loss realistic. Everything beyond five percent is flagged because the health and performance risks rise sharply.

Example and tips

An athlete walking around at 80 kg cutting to a 77 kg class with 7 days left has a 3 kg cut (3.75% of bodyweight). The tool reserves about 1.6 kg for the final-day water cut and spreads the remaining ~1.4 kg as roughly 0.23 kg per day over the preceding six days. Always rehydrate aggressively after weigh-in, and never treat a flagged cut as routine — get qualified supervision before attempting it.