Enter all but one of the weight of the arrow, acceleration due to gravity, draw length of the bow, and mass of the bow into the calculator to determine the feet per second (FPS) of the bow; this calculator can also evaluate any of the variables given the others are known.

Bow Fps Formula

The following formula is used to calculate the feet per second (FPS) of a bow:

FPS = (W * g) / (A * m)


  • FPS is the feet per second of the bow
  • W is the weight of the arrow in grains
  • g is the acceleration due to gravity (approximately 32.174 ft/s^2)
  • A is the draw length of the bow in inches
  • m is the mass of the bow in pounds

To calculate the FPS of a bow, multiply the weight of the arrow by the acceleration due to gravity, and divide the result by the product of the draw length of the bow and the mass of the bow.

What is a Bow Fps?

Bow FPS, or feet per second, is a measurement of the speed at which an arrow is launched from a bow. This is a critical factor in both hunting and target shooting as it affects the trajectory and penetration power of the arrow. The FPS of a bow is determined by several factors including the draw weight (the amount of force required to pull the bowstring back), the draw length (the distance the bowstring is pulled back), the weight of the arrow, and the efficiency of the bow itself. Higher FPS generally results in a flatter arrow trajectory and greater impact force, but it can also make the bow more difficult to draw and the arrow harder to control. Therefore, finding the right balance of FPS for a particular shooting situation is an important skill for archers.

How to Calculate Bow Fps?

The following steps outline how to calculate the Bow Fps.

  1. First, determine the draw weight of the bow (lbs).
  2. Next, determine the arrow weight (grains).
  3. Next, gather the formula from above = Bow Fps = (Arrow Weight x 7000) / (Draw Weight x 1.4).
  4. Finally, calculate the Bow Fps.
  5. After inserting the variables and calculating the result, check your answer with a bow fps calculator.

Example Problem:

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

Draw weight of the bow (lbs) = 50

Arrow weight (grains) = 350