How Much Weight Can You Cut for a Fight? (By Days Out)

Contents

How much weight you can cut depends on how much time you have. Over a fight camp, the ISSN recommends losing about 0.5–1 kg per week. In the final days, it lists suitable body-mass losses of roughly 6.7% at 72 hours, 5.7% at 48 hours and 4.4% at 24 hours before the weigh-in, with water loss alone around 2–4% in the last 24 hours (ISSN, 2025). Those are upper limits for experienced, supervised fighters with time to refill, not targets.

“How much can I cut?” is the question every fighter asks, and plenty answer it wrong. The honest version isn’t what’s possible under pressure, but what’s safe and still lets you perform.

Chronic vs acute weight loss: two different things

There are two kinds of weight loss in a cut, and mixing them up is the root of most bad cuts. Chronic loss is body fat lost over weeks and months; acute loss is water, stored carbohydrate and gut contents manipulated over hours to days before the weigh-in (Reale et al., 2017).

	Chronic (camp)	Acute (fight week)
What you lose	Mostly fat	Water, glycogen and its water, gut contents
Timescale	Weeks to months	Hours to days
Comes back after the weigh-in?	No	Yes, that’s the point
Main risk	Low energy, lost muscle, poor training	Dehydration, heat illness, kidney stress

The ACSM consensus explains that acute loss has limited effect on fat or muscle, but some loss of fat-free dry mass can happen in as little as 4 days (Burke et al., 2021). For the physiology of water weight itself, see how much water weight you can lose.

How much weight can you cut by days out?

The less time you have, the smaller the safe cut. Here’s what the position stands say for each phase:

Time before weigh-in	Guideline	Mainly from	Source
Off-camp	Stay about 12–15% above your division limit	—	ISSN, 2025
Fight camp (average 8–10 weeks)	About 0.5–1 kg per week	Fat	ISSN, 2025
Fight week	About 1–2% of body mass from lower glycogen; a similar amount from under 10 g fibre a day for 4 days	Glycogen water, gut contents	ISSN, 2025
72 hours	Up to ~6.7% of body mass in total	All acute methods combined	ISSN, 2025
48 hours	Up to ~5.7%	All acute methods combined	ISSN, 2025
24 hours	Up to ~4.4%; water loss itself ~2–4%	Mostly water	ISSN, 2025

The ACSM puts a more cautious line on the water part: losing fluid at the level you’d see in normal training (e.g. 2–3% of body mass) is likely to have few disadvantages if you recover aggressively after the weigh-in, while relying on it for more than 3% may have substantial negative effects on health and performance (Burke et al., 2021).

The practical takeaway: get most of the way with camp nutrition, use glycogen and fibre for the next slice, and keep the water cut small. Our water loading guide and sauna weight cut guides cover the last step.

It depends on the gap between weigh-in and fight

Your recovery window decides how much acute loss you can reverse. The time available after the weigh-in determines what degree of acute loss can be used and undone (Reale et al., 2017).

• Day-before weigh-in (pro MMA, pro boxing): these sports can offer up to 32 hours of recovery (Burke et al., 2021). That window is what makes a planned acute cut reversible.
• Same-day weigh-in (many amateur events): in Olympic combat sports weigh-ins happen anywhere from 3 to 24 hours before competing (Reale et al., 2017). With only a few hours, you can’t refill a big water cut, so you should arrive close to the limit.
• Tournaments with repeat weigh-ins: you have to make weight again each day, so every cut has to be small.

A worked example

Say you weigh 80 kg off-camp and want to fight at −70 kg, with an 8-week camp and a day-before weigh-in.

Phase	Target	Check against the guidelines
Off-camp	80 kg	70 kg + 12–15% = 78.4–80.5 kg, so you’re inside the range
8-week camp	Lose ~6.5 kg to ~73.5 kg	~0.8 kg per week, inside 0.5–1 kg
Final 72 hours	Lose ~3.5 kg to 70 kg	~4.8% of 73.5 kg, under the ~6.7% ceiling

That plan works, but it has little margin. If camp goes badly and you walk into fight week at 75 kg, you’d need 5 kg (6.7%) in 72 hours, right at the ceiling. That’s the moment to talk about the weight class, not to book more sauna time. Your weekly check-ins should show the trend heading toward about 73–74 kg, not still near 80.

What do common targets in pounds mean?

Whether a number is “a lot” depends on your size, so convert it to a percentage of your current weight:

Your weight	5 lb (2.3 kg) is…	10 lb (4.5 kg) is…
150 lb (68 kg)	3.3%	6.7%
170 lb (77 kg)	2.9%	5.9%
200 lb (91 kg)	2.5%	5.0%

Compare those with the table above. Five pounds in a week is usually within reach with a day-before weigh-in. Ten pounds in the last few days is at or above the ISSN’s 72-hour figure for most fighters, so it needs to come mostly from camp.

Have you picked the wrong weight class?

If the numbers only work with a huge water cut, the class is wrong. Warning signs:

• Off-camp, you sit well above 15% over your division limit.
• Your plan relies on losing more than about 3% as water (the ACSM threshold above).
• Training falls apart because calories have been too low for too long.
• You’re already lean, and there’s no “easy” weight left to take off.

Extreme cuts do happen. The largest changes in a systematic review came from two MMA cohorts, who lost about 7.4 kg (~10%) before the weigh-in (Matthews et al., 2019). In a documented case, an MMA athlete lost 18.1% of his body mass over 8 weeks, including 9.3% through dehydration in the final 24 hours, and developed acute kidney injury (Kasper et al., 2019). Neither is a model.

If the signs fit, the honest and often stronger answer is a higher weight class. Our combat sports weight classes chart shows where you’d land.

Want your own numbers? The weight cut calculator shows the weekly pace you’d need and what’s left for fight week.

Does being heavier actually help?

Less than most fighters think. The ACSM notes that extra body mass seems to help in grappling sports like wrestling and judo, while in striking, height and reach are only partly tied to weight. In MMA, studies have not found a link between how much weight fighters regain after the weigh-in and whether they win (Burke et al., 2021).

How to know you’re on track

• Weigh yourself every morning after the toilet, before food and drink. Look at the 1–2-week trend, not single days.
• Losing faster than about 1 kg per week? Eat a little more; going faster than the ISSN range risks muscle and training quality.
• Stalled for two weeks? Adjust intake slightly. See fight camp calories and macros.
• Count backward from the weigh-in: how many kilos, over how many weeks, at what pace?

MyFightPrep counts backward from your fight date, tracks your weight trend day by day and shows whether your weight class is realistic — free.

Important

This guide is general information, not medical advice. The numbers above are upper limits for experienced adults with supervision and time to recover, not targets. Heavy cuts and dehydration can be dangerous. If you’re under 18, new to the sport, have a medical condition or are in doubt, choose your weight class with your coach and a doctor, and cut less than you think you can. If you feel dizzy, confused or unwell during a cut, stop and seek help.

Frequently asked questions

Can I cut 10 pounds in 2 weeks?

It depends on your size. Ten pounds is about 6.7% of body weight for a 150 lb fighter but 5% for a 200 lb fighter. With a day-before weigh-in, a heavier, experienced fighter can sometimes combine 1–2 kg of real loss over two weeks with a planned final-days cut, but for lighter fighters it goes past the ranges the ISSN describes. Plan with your coach, or pick a heavier class.

Can I cut 5 pounds in a week?

For most adult fighters with a weigh-in the day before, yes. Five pounds is about 2.3 kg, roughly 2.5–3.3% of body weight for a 150–200 lb fighter, which fits inside the ISSN's ranges for the final days through lower carbs, lower fibre and a modest water cut. With a same-day weigh-in, aim to be much closer to the limit.

How long should I weigh cut?

The gradual part should run through your whole camp, which the ISSN says averages 8–10 weeks, at about 0.5–1 kg per week. The acute part, glycogen, fibre and water, belongs in the final days, with any water cut concentrated in the last 24 hours before the weigh-in.

Does 10 pounds make a difference in a fight?

Sometimes. The ACSM notes that extra body mass seems to help in grappling sports like wrestling and judo, while in MMA studies have not found a link between weight regained after the weigh-in and winning. What is clear is that a big cut can cost you health and performance, so being in the right class matters more than being the bigger fighter.

Sources

This guide is based on the works below. Numbers in the text refer to them.

1. Ricci AA, Evans C, Stull C, et al. (2025). International society of sports nutrition position stand: nutrition and weight cut strategies for mixed martial arts and other combat sports
2. Burke LM, Slater GJ, Matthews JJ, Langan-Evans C, Horswill CA (2021). ACSM Expert Consensus Statement on Weight Loss in Weight-Category Sports
3. Reale R, Slater G, Burke LM (2017). Acute-Weight-Loss Strategies for Combat Sports and Applications to Olympic Success
4. Reale R, Slater G, Burke LM (2017). Individualised dietary strategies for Olympic combat sports: Acute weight loss, recovery and competition nutrition
5. Matthews JJ, Stanhope EN, Godwin MS, Holmes MEJ, Artioli GG (2019). The Magnitude of Rapid Weight Loss and Rapid Weight Gain in Combat Sport Athletes Preparing for Competition: A Systematic Review
6. Kasper AM, Crighton B, Langan-Evans C, et al. (2019). Case Study: Extreme Weight Making Causes Relative Energy Deficiency, Dehydration, and Acute Kidney Injury in a Male Mixed Martial Arts Athlete