Enter the underwater volume, length, width, and draft of the ship into the calculator to determine the block coefficient.

Block Coefficient Formula

The following formula is used to calculate the block coefficient.

CB = V / (L * B * T)

Variables:

  • CB is the block coefficient (dimensionless)
  • V is the underwater volume of the ship (m³)
  • L is the length of the ship (m)
  • B is the width of the ship (m)
  • T is the draft of the ship (m)

To calculate the block coefficient, divide the underwater volume of the ship by the product of its length, width, and draft. A higher block coefficient indicates a fuller hull shape, while a lower value suggests a more streamlined or slender design.

What is a Block Coefficient?

The block coefficient is a dimensionless value used in ship design to represent how much of the volume of a rectangular block, with dimensions equal to the length, width, and height of the ship, is filled by the ship’s hull. It is calculated by dividing the underwater volume of the ship by the product of its length, width, and draft. A higher block coefficient indicates a fuller hull shape, while a lower value suggests a more streamlined or slender design.

How to Calculate Block Coefficient?

The following steps outline how to calculate the Block Coefficient (CB).


  1. First, determine the underwater volume of the ship (V) in cubic meters (m³).
  2. Next, determine the length of the ship (L) in meters (m).
  3. Next, determine the width of the ship (B) in meters (m).
  4. Next, determine the draft of the ship (T) in meters (m).
  5. Finally, use the formula CB = V / (L * B * T) to calculate the Block Coefficient.

Example Problem:

Use the following variables as an example problem to test your knowledge.

Underwater volume of the ship (V) = 500 m³

Length of the ship (L) = 30 m

Width of the ship (B) = 10 m

Draft of the ship (T) = 5 m