Muay Thai weight classes depend on whether you fight under amateur or professional rules. IFMA uses kilogram-based divisions for amateur competition, while WBC Muaythai uses named divisions with pound and kilogram limits for professional bouts. Check the rules for your event before picking a target weight.
Amateur Muay Thai weight classes: IFMA
| Men (kg) | Men (lb) | Women (kg) | Women (lb) |
|---|---|---|---|
| 48 | 105.8 | 45 | 99.2 |
| 51 | 112.4 | 48 | 105.8 |
| 54 | 119.0 | 51 | 112.4 |
| 57 | 125.7 | 54 | 119.0 |
| 60 | 132.3 | 57 | 125.7 |
| 63.5 | 140.0 | 60 | 132.3 |
| 67 | 147.7 | 63.5 | 140.0 |
| 71 | 156.5 | 67 | 147.7 |
| 75 | 165.3 | 71 | 156.5 |
| 81 | 178.6 | 75 | 165.3 |
| 86 | 189.6 | ||
| 91 | 200.6 | ||
| over 91 | over 200.6 | over 75 | over 165.3 |
Source: IFMA Rules and Regulations v3.057. A men’s 45 kg class is used only at selected multi-sport events. Pounds converted.
The IFMA table is the place to start if you are entering an amateur Muay Thai event. Read the division label and weight limit together. Do not choose a class just because it sounds close to your training weight.
The IFMA Masters and Elite men’s list includes a 45 kg class only for selected multi-sport events; Masters athletes in the 40+ and 45+ groups cannot enter +91 kg; and the women’s list ends with +75 kg IFMA
If you think in pounds, use the conversions for reference. Keep the official kilogram limit in mind when you talk to your coach. Do not aim right at the edge of a class.
Before signing up, confirm that your category and division are offered. Ask when to report for the scale. Check these details before making a weight plan.
IFMA weigh-in rules
IFMA uses different weigh-in checkpoints around competition. Understand the schedule before planning meals, training, travel, or recovery. Do not count on repeat attempts to reach your desired number.
Under IFMA rules, an Official Weigh-In may be held 1 day before competition if the Technical Delegate chooses; a Competition Weigh-In takes place each competition morning; a Pre-Contest Weigh-In may happen before or after the bout; competition cannot begin until at least 3 hours after the Competition Weigh-In closes; an athlete gets only 1 official scale attempt per day’s weigh-in, wearing light undergarments; a pre-contest reading 5% above the class limit or at the next class’s weight means disqualification; and the Technical Delegate may approve a 0.5 kg allowance for a U24 athlete with travel problems IFMA
Rule check: Treat the official scale reading as final. Do not build a plan around the hope of a second try or an informal exception. If travel has affected your arrival, speak with the event staff instead of assuming an allowance applies automatically.
Eat regular meals, stay normally hydrated, and tell your coach if you feel pressure to lose weight fast. A weigh-in is not a test of how much discomfort you can tolerate.
Pro Muay Thai weight classes: WBC Muaythai
| # | WBC Muaythai division | Limit (lb) | Limit (kg) |
|---|---|---|---|
| 1 | Minimumweight (women only) | 100 | 45.359 |
| 2 | Mini-Flyweight | 105 | 47.627 |
| 3 | Light Flyweight | 108 | 48.987 |
| 4 | Flyweight | 112 | 50.802 |
| 5 | Super Flyweight | 115 | 52.163 |
| 6 | Bantamweight | 118 | 53.524 |
| 7 | Super Bantamweight | 122 | 55.338 |
| 8 | Featherweight | 126 | 57.153 |
| 9 | Super Featherweight | 130 | 58.967 |
| 10 | Lightweight | 135 | 61.235 |
| 11 | Super Lightweight | 140 | 63.503 |
| 12 | Welterweight | 147 | 66.678 |
| 13 | Super Welterweight | 154 | 69.853 |
| 14 | Middleweight | 160 | 72.575 |
| 15 | Super Middleweight | 168 | 76.204 |
| 16 | Light Heavyweight | 175 | 79.379 |
| 17 | Cruiserweight | 200 | 90.719 |
| 18 | Heavyweight | over 200 | over 90.718 |
Source: WBC Muaythai rules.
WBC Muaythai uses named divisions such as Flyweight, Featherweight, Lightweight, Welterweight, and Heavyweight. Some names also appear in boxing, so check the exact Muay Thai limit rather than relying on the name.
Ask for the exact contracted division and weigh-in instructions. If you have competed as an amateur, do not carry over your old class without checking the professional table.
You can compare these divisions with boxing weight classes, but use the Muay Thai rules for your fight.
WBC Muaythai weigh-ins and safety checks
For a professional bout, get the weigh-in time and pre-fight requirements early. A class that looks manageable on paper may be a poor fit if it calls for last-minute changes to your food or water habits.
WBC Muaythai normally weighs fighters 24 to 30 hours before the scheduled fight, without clothing although underwear is permitted; same-day weigh-ins are an exception, including certain title bouts in Thailand; its safety checks call for no more than 10% above the bout limit at 30 days, 5% at 14 days, and 3% at 7 days; and a fighter who misses championship weight cannot win the title, with the bout allowed to proceed only if that fighter is no more than 2.2 kg (5 lb) over WBC Muaythai
Safety: The checks are not weight loss targets. Do not treat a last-minute drop or dehydration as a normal part of preparation.
Talk to your coach and the event staff well before the official check. If your current weight is far from the limit, consider another division rather than trying to solve the gap with a rushed cut. After the scale, focus on a reasonable food and fluid routine rather than trying to undo an extreme cut. The rehydration calculator can help you organize that conversation.
Muay Thai rules for youth fighters
Young fighters need clear boundaries. Parents and coaches should confirm the event rules rather than assuming adult title rules apply.
For WBC Muaythai U18 and U16 titles, an overweight fighter has 2 hours to make weight with unlimited attempts, and sauna suits are not allowed WBC Muaythai
Safety: Extra attempts do not make unsafe methods acceptable. Sauna suits, rubber or plastic suits, spitting, diuretics, laxatives, vomiting, and deliberate water restriction are dangerous ways to chase a number. The better response to a weight problem is to involve a parent, coach, and qualified health professional before the event, and to consider a division that fits the athlete’s usual condition.
Parents should ask how weigh-ins are supervised. Your athlete should be able to speak up if a plan makes training, school, or daily life harder. Health comes before making the scale.
Choosing a Muay Thai weight class safely
Start with your weight under normal eating and drinking conditions. Compare it with the official divisions and weigh-in schedule. Choose a class that lets you eat, drink, train, and recover normally.
| Your situation | A sensible next step |
|---|---|
| You are close to a listed limit | Confirm the official weigh-in instructions with your coach. |
| You are well above the limit you want | Discuss moving to a higher division instead of rushing a cut. |
| You are switching from amateur to pro | Check the WBC Muaythai table rather than reusing an IFMA class. |
| You are a young fighter | Bring a parent or guardian into the class decision. |
The weight cut calculator can show the gap between your current weight and the limit you are considering. Treat that as information for a decision, not permission to lose the weight quickly. A large gap is a reason to question the class, not a challenge to beat the clock.
Avoid saunas, sweat suits, skipped fluids, or fasting to force a lower reading. If your coach, parent, or medical professional thinks the target is too aggressive, choose a more suitable class.
What to do next
Choose your division from the correct table. Confirm it with the organizer and ask for weigh-in instructions. Share those details with your coach and, if you are young, a parent or guardian.
If you need help organizing meals and the time around the weigh-in, CutCoach builds a day by day plan for calories, water, meals, and refueling after the scale from your weight, weight class, and weigh-in date. It is available on iPhone and Android. Use planning tools to support sensible choices, not to push into a division that is a poor fit.
The right class may be the one closest to your normal training weight. Aim to arrive ready to compete, not just relieved that you made the scale.