Arrow Speed Calculator

Using the bow speed IBO specification, our easy Arrow Speed Calculator estimates arrow speed, momentum, and kinetic energy. All you have to do is enter the bow's IBO rating, length, draw weight, arrow weight, and additional string weight, then press the calculate button to get the results.

Arrow Speed Calculator: If you're having trouble calculating the speed of an arrow, don't worry; you can use this simple calculator tool to assist you out. It calculates the exact arrow speed as well as momentum and kinetic energy. Continue reading to learn about the IBO specification for bow speed, archery speed principles, formulae, and techniques for calculating arrow speed.

Understanding the IBO specification for bow speed

The IBO (International Bowhunting Organization) specification is used by the majority of professional bows. If you keep the following characteristics in mind, this specification will determine the arrow speed

  • The draw length is 30 inches,
  • The draw weight is 70 pounds, and
  • The arrow weighs 350 grains.

If you change these settings, the arrow speed will not match the one specified in the specification. However, Most archers do not employ these exact criteria. This is where the bow speed calculator comes in helpful; it allows you to experiment with different bow settings to see how the arrow reacts.

Principles of Archery Calculator

The following criteria should be used to modify the IBO-specified arrow speed

  • For each inch of draw length less than 30′′, subtract 10 ft/s from the IBO value.
  • For every inch of draw length beyond 30′′, add 10 ft/s to the IBO value.
  • For every 3 grains of total arrow weight overdraw weight multiplied by 5, subtract 1 ft/s from the IBO value.
  • For every 3 grains of additional weight on the bowstring, subtract 1 ft/s from the IBO number.

All of these rules can be summed up as follows v = IBO + (L - 30) * 10 - W / 3 + min (0, -(A - 5D)/3)

  • Where, v = actual arrow speed in ft/s,
  • IBO is the arrow speed according to the IBO specification in ft/s,
  • L = draw length in inches,
  • W = additional weight on the bowstring in grains,
  • A = arrow weight in grains, and
  • D = draw weight in pounds.

You may also use the arrow speed calculator to calculate the arrow's momentum and kinetic energy. These are calculated in the following way

  • Momentum = A * v
  • Kinetic energy = A *v^2 / 2

The units are automatically converted using our arrow speed calculator. If you're doing all of these calculations by hand, keep track of the units you're using

How to Calculate the Speed of an Arrow?

To quickly verify the arrow speed, follow these easy rules and guidelines.

  • Step 1:Examine the question for the necessary information.
  • Step 2: Subtract 30 from the length of the sketch and multiply it by 10.
  • Step 3: Three times the added weight is divided on the bowstring
  • Step 4: Subtract step 2's result from step 3's result.
  • Step 5: Fill in the blanks in the IBO with the outcome.

For more concepts check out to get quick answers by using this free tool.

Arrow Speed Calculation Example

Question 1: If the draw length is 42 inches, the BOW IBO rating is 450 ft/s, the draw weight is 80 lbs, the arrow weight is 600 grains, and the additional weight is 6 grains. How do you calculate the arrow's speed and kinetic energy?



Bow IBO rating = 450 ft/s

Draw length L = 42 in

Additional weight on the bow W = 6 grains

Draw weight D = 80 lbs

Arrow weight A = 600 grains

Arrow speed v = IBO + (L - 30) * 10 - W / 3 + min (0, -(A - 5D)/3)

v = 450 + (42 - 30) x 10 - 6/3 + min(0, -(600 - 5 x 80)/3)

= 450 + 120 - 2 + min(0, -(600 - 400)/3)

= 568 - 66.67

= 501.33

Hence, the speed of the arrow is 501.33 ft/s.

FAQs on Arrow Speed Calculator

1. Is it true that arrow speed calculators are accurate?

The precision of the IBO rating on the bow determines the accuracy of the calculation, and different manufacturers utilise varying tolerances for draw length and draw weight.

2. Is arrow speed affected by the length of the draw?

The greater your draw length is, the longer your bow's power stroke is, and the faster your bow shoots. As a matter of thumb, 1 inch of draw length equals around 10 feet per second of arrow velocity.

3. Is it true that lighter arrows go faster?

Lighter arrows fly quicker and can form tighter groups, but they're more difficult to tune. Heavier arrows go slower, but they are more resistant to wind and penetrate further.

4. Is it faster to shoot an arrow or a bullet?

Arrows travel at a slower rate than bullets. The speed of an arrow is determined by the archer's and bow's capabilities. The fastest bow's arrow travels at 360 feet per second, whereas the slowest bullet travels at 400 feet per second. Bullets are thus faster than arrows.