There are currently 17 weight classes in mens professional boxing, ranging from strawweight (105 lbs) to heavyweight (200+ lbs) . The weight classes and their upper limits, as recognized by professional governing bodies, are as follows:

• Strawweight: 105 lbs (48 kg)
• Junior Flyweight: 108 lbs (49 kg)
• Flyweight: 112 lbs (51 kg)
• Junior Bantamweight: 115 lbs (52 kg)
• Bantamweight: 118 lbs (53.5 kg)
• Junior Featherweight: 122 lbs (55.3 kg)
• Featherweight: 126 lbs (57.2 kg)
• Junior Lightweight: 130 lbs (59 kg)
• Lightweight: 135 lbs (61.2 kg)
• Junior Welterweight: 140 lbs (63.5 kg)
• Welterweight: 147 lbs (66.7 kg)
• Junior Middleweight: 154 lbs (69.9 kg)
• Middleweight: 160 lbs (72.6 kg)
• Super Middleweight: 168 lbs (76.2 kg)
• Light Heavyweight: 175 lbs (79.4 kg)
• Cruiserweight: 200 lbs (90.7 kg)
• Heavyweight: 200+ lbs (90.7+ kg)

It's worth noting that different sanctioning bodies may use slightly different weight limits for each division.