How many weight classes are in professional boxing?

There are 17 traditional weight divisions recognized by the Association of Boxing Commissions (ABC) and major sanctioning bodies, with an 18th division called Bridgerweight (224 lbs / 101.6 kg) recognized by the WBC and WBA.

What is the IBF second-day weigh-in rehydration rule?

On the morning of an IBF championship bout, fighters must step on the scales and weigh no more than 10 lbs (4.54 kg) above the contract weight limit. This rule does not apply to unification bouts.

⚖️ WBC • WBA • IBF • WBO • ABC Official Regulatory Standard

BOXING WEIGHT CLASSES & REHYDRATION

The official technical directory for all 18 professional boxing weight divisions in order. Features exact limits in pounds and kilograms, regulated glove sizes, the official WBC 30, 14, and 7-Day Safety Scales, the IBF 10-lb Morning Weigh-In rules, and penalty structures for missing weight.

THE 18 PROFESSIONAL BOXING WEIGHT DIVISIONS (IN ORDER)

# Division	Alternate Name	Weight Limit (lbs)	Weight Limit (kg)	Glove Size
#1 Strawweight	Mini Flyweight / Minimumweight	105 lbs	47.63 kg	8 oz
#2 Light Flyweight	Junior Flyweight	108 lbs	48.99 kg	8 oz
#3 Flyweight	Traditional Flyweight (Original 8)	112 lbs	50.80 kg	8 oz
#4 Super Flyweight	Junior Bantamweight	115 lbs	52.16 kg	8 oz
#5 Bantamweight	Traditional Bantamweight (Original 8)	118 lbs	53.52 kg	8 oz
#6 Super Bantamweight	Junior Featherweight	122 lbs	55.34 kg	8 oz
#7 Featherweight	Traditional Featherweight (Original 8)	126 lbs	57.15 kg	8 oz
#8 Super Featherweight	Junior Lightweight	130 lbs	58.97 kg	8 oz
#9 Lightweight	Traditional Lightweight (Original 8)	135 lbs	61.24 kg	8 oz
#10 Super Lightweight	Junior Welterweight / Light Welter	140 lbs	63.50 kg	8 oz
#11 Welterweight	Traditional Welterweight (Original 8)	147 lbs	66.68 kg	8 oz
#12 Super Welterweight	Junior Middleweight / Light Middle	154 lbs	69.85 kg	10 oz
#13 Middleweight	Traditional Middleweight (Original 8)	160 lbs	72.58 kg	10 oz
#14 Super Middleweight	Super Middle	168 lbs	76.20 kg	10 oz
#15 Light Heavyweight	Traditional Light Heavy (Original 8)	175 lbs	79.38 kg	10 oz
#16 Cruiserweight	Junior Heavyweight	200 lbs	90.72 kg	10 oz
#17 Bridgerweight	WBC & WBA (Created 2020)	224 lbs	101.61 kg	10 oz
#18 Heavyweight	Unlimited (>200 lbs / >224 lbs WBC)	Unlimited	Unlimited	10 oz

WBC Safety Weight Scale (30, 14, 7 Days)

The WBC mandates periodic safety weigh-ins to protect fighters from deadly acute dehydration before title bouts:

30 Days Out: Maximum +10% above weight class limit.
14 Days Out: Maximum +5% above weight class limit.
7 Days Out: Maximum +3% above weight class limit.
Official Weigh-In (24–36 hrs): 100% of division limit.

IBF 10-lb Morning Weigh-In Rule

The IBF conducts a compulsory morning weigh-in on the day of the bout between 8:00 AM and 10:00 AM:

Boxers can rehydrate no more than 10 pounds (4.54 kg) over contract weight.
Fighters exceeding the 10-lb rehydration ceiling lose their title or title eligibility.
Unification Exemption: Per official IBF guidelines, the second-day weigh-in is waived for title unification bouts.

WHAT HAPPENS WHEN A BOXER MISSES WEIGHT?

1. 2-Hour Extension Boxers are allowed up to two hours to shed excess pounds using non-drug methods under ringside physician supervision.

2. 35% to 45% Purse Fines Overweight fighters forfeit 35% of their total purse (25% to promoter, 10% to opponent). Refusal to re-weigh raises the fine to 45%.

3. Title Vacated on Scales A champion missing weight forfeits the title immediately. If the challenger wins, they become champion; if the overweight fighter wins, the belt stays vacant.

WEIGHT CLASS & REHYDRATION FAQS

How many weight classes are there in professional boxing?

There are 17 traditional weight divisions recognized by the ABC and all major sanctioning bodies, with an 18th division (Bridgerweight at 224 lbs) introduced by the WBC and WBA.

When do glove sizes change from 8 oz to 10 oz?

Glove sizes transition from 8 oz to 10 oz at 154 lbs (Super Welterweight). All divisions at or below 147 lbs (Welterweight) use 8 oz gloves.

What is the IBF 10-lb rehydration rule?

On the morning of an IBF championship fight, boxers must step on the scale again and weigh no more than 10 lbs above their division limit. Unification bouts are exempt.