Boneyard Tools

Archery Draw Length Calculator

Measure your arm span fingertip to fingertip and divide by 2.5 to estimate your draw length. No arm span handy? Height works as a close stand-in for most archers.

How to estimate draw length

  1. Stand against a wall and stretch both arms out level, palms forward.
  2. Measure your arm span in inches from one middle fingertip to the other.
  3. Read the estimated draw length below, which is arm span divided by 2.5.

Examples

70 inch arm span

wingspanIn 70
Estimated draw length 28 in

Frequently asked questions

How is draw length calculated from arm span?

The standard AMO estimate divides your arm span in inches by 2.5. An arm span of 70 inches gives 70 / 2.5 = 28 inches of draw length, a common starting point for fitting a bow.

Can I use my height instead of arm span?

Yes. For most people arm span is close to height, so dividing height in inches by 2.5 gives a similar estimate. Arm span is more accurate, so use it when you can measure it.

Is this draw length exact?

No, it is an estimate. Draw form, anchor point and release style all shift the real number. Treat the result as a starting point and confirm at a pro shop before buying a bow.

Why divide by 2.5?

The Archery Manufacturers Organization adopted dividing arm span by 2.5 as a simple, repeatable rule that lands close to the measured draw length for the average archer.

What if my arm span and height differ a lot?

Prefer the arm span figure, since draw length tracks reach more than standing height. If they differ widely, get measured in person with a draw length arrow on a bow.

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