Arrow Calculators - Professional Suite

📏 IBO Speed (fps) – Measured Value

IBO speed is the arrow velocity measured under International Bowhunting Organization (IBO) standard conditions: a bow set at 80 lbs draw weight, 30 inches draw length, shooting a 350-grain arrow from a height of 5 feet, with the average of three shots recorded. Your actual arrow speed will vary based on your draw weight, draw length, and arrow weight. Enter your bow's rated IBO speed here.

📐 Shaft Length (inches) – Measured Value

Shaft length is measured from the throat of the nock to the end of the shaft (excluding the point). For custom arrows, it is typically your draw length plus 1 to 1.5 inches of safety margin. Measure an existing arrow or estimate based on your draw length.

📋 How to Use These Calculators

Shared Parameters: All input fields (IBO speed, draw weight, shaft GPI, etc.) are linked across calculators. Changing a value in any card will automatically update the same field in all other cards.
Recalculation Required: After modifying any parameter, you must click the "Click for ..." button of the desired calculator to get updated results. Results do not update automatically.
Arrow Comprehensive Properties Calculator provides the most complete set of arrow characteristics, including speed (also known as Arrow FPS calculator, Speed of an Arrow calculator, Archery FPS calculator, or Backcountry Archery calculator), kinetic energy, momentum, FOC, and suggested spine.
Use the specialized calculators for quick access to specific values: Arrow Weight, Arrow Spine, and Shaft Diameter (with three calculation modes). In the diameter calculator, you can enter values in either mm or inches – they will automatically convert.

Arrow Weight Calculator

Shaft GPI:

Shaft Length (in):

Point (grains):

Fletching (grains):

Nock (grains):

Wrap (grains):

Total Arrow Weight:0grains

Calculate Arrow Spine

Draw Weight (lbs):

Draw Length (in):

Shaft GPI:

Shaft Length (in):

Point (grains):

Fletching (grains):

Nock (grains):

Wrap (grains):

Suggested Spine:0

Arrow Comprehensive Properties Calculator

IBO Speed (fps):

Draw Weight (lbs):

Draw Length (in):

Shaft GPI:

Shaft Length (in):

Point (grains):

Fletching (grains):

Nock (grains):

Wrap (grains):

Total Weight:0gr

Speed (FPS):0fps

Kinetic Energy:0ft-lbs

Momentum:0slug-ft/s

FOC:0%

Spine:0

Arrow Shaft Diameter Calculator

Wall Thickness:0.00mm

Wall Thickness (in):0.000in

Formula:

📏 FOC Calculation Note

The current FOC calculation in the calculators is only based on point weight percentage and is for reference only. The true FOC = (Balance Point Distance - Shaft Length/2) / Shaft Length, where Balance Point Distance is measured from the nock throat to the arrow's balance point. Calculating the balance point requires knowing the weight and position of each component, which is not possible with the current parameters. Therefore, you can measure the actual FOC by following the DIY method (Find the Balance Point (5-Minute DIY Method)).

🏹 Professional Arrow Calculators