  # Calculating Constant Force on a Coil Compression Spring

#### Definition

The calculation of the amount of constant force it takes a coil compression spring to compress down to a loaded height is calculated by multiplying the force by the distance the coil compression spring is expected to travel. The unit of measurement for constant force is lbf/in which stands for pounds of force per inch.

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#### Example:

A spring of 12” (inches) has to travel 5” to a loaded height of 7” with a load or force of 5 lb. (pounds).

k = F ÷ x
k = 5 ÷ 5
k = 1 lbf/in (pounds of force per inch)

F = Force
x = Distance Traveled
k = Constant or Rate