Enter the total mass held by the bridge and the total mass of the bride itself into the calculator to determine the bridge efficiency.

Bridge Efficiency Formula

The following equation is used to calculate the Bridge Efficiency.

BE = MS / MB
  • Where BE is the bridge efficiency
  • MS is the mass supported by the bridge at maximum capacity
  • MB is the mass of the bridge

To calculate the bridge efficiency, divide the mass supported by the bridge as maximum capacity by the total mass of the bridge itself.

What is a Bridge Efficiency?


Bridge efficiency is a measurement of a bridge’s total structural efficiency. Structural efficiency is the relationship between the weight of a structure and the strength of its support. The lower the weight, the higher the structural efficiency, and therefore the better the bridge.

Bridge efficiency quantifies a suspension bridge’s total structural efficiency. A low-weight structure needs less support to carry the same loads as a heavier structure, so it is more structurally efficient. The Golden Gate Bridge, often referred to as an icon and a miracle of engineering, has world’s best overall bridge efficiency (91.3%).

If a bridge is properly designed, it can serve its intended purpose for many years. The relationship between the weight and the strength of a bridge are essential to achieving this longevity.