Panamax Dimensions: Size Limits for Ships in the Panama Canal

The Panama Canal's original locks impose strict size limits known as Panamax dimensions:

• Maximum length: 965 feet (294 meters)
• Maximum width (beam): 106 feet (32 meters)
• Maximum draft: 39.5 feet (12 meters)
• Maximum height above waterline: 190 feet (58 meters)

Ships exceeding these dimensions are classified as "post-Panamax" and cannot transit the original locks. The 2016 expansion added larger Neopanamax locks, accommodating ships up to 1,200 feet long, 161 feet wide, and 50 feet draft. Vessels too large for even the new locks must sail around Cape Horn or offload cargo.