Enter the length of the side (ft) and the length of the beam (ft) into the Length to Beam Ratio Calculator. The calculator will evaluate and display the Length to Beam Ratio. 

Length to Beam Ratio Formula

The following formula is used to calculate the Length to Beam Ratio. 

LBR = L / B
  • Where LBR is the Length to Beam Ratio (length:beam)
  • L is the length of the side (ft) 
  • B is the length of the beam (ft) 

To calculate the length to beam ratio, simply divide the length of the side by the length of the beam.

How to Calculate Length to Beam Ratio?

The following example problems outline how to calculate Length to Beam Ratio.

Example Problem #1:

  1. First, determine the length of the side (ft).
    • The length of the side (ft) is given as: 50.
  2. Next, determine the length of the beam (ft).
    • The length of the beam (ft) is provided as: 25.
  3. Finally, calculate the Length to Beam Ratio using the equation above: 

LBR = L / B

The values given above are inserted into the equation below and the solution is calculated:

LBR = 50 / 25 = 2:1 (length:beam)


Example Problem #2: 

For this problem, the variables required are provided below:

length of the side (ft) = 75

length of the beam (ft) = 30

Test your knowledge using the equation and check your answer with the calculator above.

LBR = L / B = ?