Weight cutting in the UFC and other mixed martial arts is a crucial process for fighters. To compete in a specific weight class, they must weigh in under a certain limit; otherwise, they won’t be allowed to face their desired opponents and will have to move up to the next division.

The UFC has 8 male weight classes, from flyweight to heavyweight, and 9 total if we include strawweight in the women’s division. Understanding the requirements fighters must meet—and how they handle the before and after of the weight cut—is essential when placing smart bets.

The UFC Weight Cutting Process

Due to its importance and complexity, many refer to the weight cut as “Round 0” of any UFC fight. But what exactly is a weight cut, and why is it so impactful?

To understand this, you need to know that fighters are divided into weight classes determined by their weigh-in the day before the fight. If they exceed the maximum allowed weight, they’re disqualified from competing. That’s why many fighters aim to lose between 10 and 15 kilograms (22–33 pounds) before the fight, to compete in a more favorable weight class. However, to perform well, they must regain as much of that lost weight as possible before stepping into the cage.

To do this, fighters follow a strict diet starting roughly three months before the bout, with the most extreme phase happening in the final week. During that time, they reduce food intake and may drink up to 10 liters (over 2.5 gallons) of water per day. Then, the day before the weigh-in, they begin an extreme dehydration phase, where they can lose up to 10 kilograms (22 pounds) in just a few hours.

After the weigh-in, they immediately begin rehydrating and refueling, trying to recover as much of the lost weight as possible in less than 24 hours.

How Does Weight Cutting Affect Fighter Performance?

Weight cutting in the UFC is a demanding procedure, and not all fighters are equally prepared for it. Some may struggle to regain the lost weight, which can result in a noticeable difference—especially if one fighter steps into the octagon 3 kilograms (6–7 pounds) heavier than the other.

The impact isn’t only physical—it also affects fighters mentally and emotionally. Poor recovery can reduce striking power and endurance, while also affecting focus, reaction time, and mental sharpness.

And just because a fighter has successfully cut and regained weight in the past doesn’t mean they’ll do it smoothly every time. That’s why monitoring fighters closely in the hours leading up to a fight can give you a betting edge.

Is Weight Cutting Dangerous in the UFC?

Weight cutting in MMA (including the UFC) offers competitive advantages, but it also poses serious health risks. That’s why it’s a critical factor to consider when betting on UFC fights.

Extreme dehydration, electrolyte imbalances, and overall physical and mental stress can sometimes prevent fighters from making it into the octagon—even after a successful weigh-in.

That’s why fighters like Spain’s Ilia Topuria rely heavily on professional nutritionists and health teams. In addition to physical preparation, they require mental toughness well above the norm—even if every athlete has their own challenges.

How Weight Cutting Impacts UFC Odds and Betting Strategies

The UFC’s extreme weight-cutting culture can dramatically change betting odds from one day to the next. In fact, you can even bet on whether a fighter will make weight or not. But once that hurdle is cleared, the real key lies in how much weight they regain and how sharp they look on fight day.

For example, in the featherweight division—where Topuria competes—fighters must weigh below 65.8 kg (145 pounds). But not by too much: every gram counts when it’s time to face off.

From there, both fighters have until the fight to regain as much weight as possible. That’s why live UFC betting is so exciting—it lets you adapt your picks in real time based on how each fighter looks in the cage.

UFC Weight Classes and Limits