Archer Draw Length Calculator
Calculate your correct bow draw length from your wingspan or arm span.
Proper draw length is essential for accuracy, consistency, and injury prevention.
What draw length is
Draw length is the distance from the bowstring at full draw to the throat of the grip, plus 1¾ inches (the AMO measurement convention used on every modern compound bow). It is the single most important fit dimension in archery. Too long and you over-extend, lose your back tension, and your arrows pluck off the rest. Too short and you lose anchor consistency, peep alignment, and stored energy.
The wingspan rule
Stand naturally with your arms stretched out to the sides, palms facing forward, shoulders relaxed. Measure tip of middle finger to tip of middle finger. That is your wingspan. Divide by 2.5 to get a starting draw length in inches:
- 175 cm wingspan (5'9" person) → 27.6 in draw
- 183 cm wingspan (6'0" person) → 28.8 in draw
- 190 cm wingspan (6'3" person) → 29.9 in draw
The rule is good enough that most pro shops use it as their first guess, then fine-tune from there.
Why fit matters more on a compound
Compound bows are not infinitely adjustable. Each cam set has a specific draw length range, usually 25 to 30 inches or 28 to 32 inches, and the bow only delivers its rated speed and let-off at the correct setting. A draw length that is half an inch off costs accuracy, adds shoulder strain over a long shoot, and can void IBO speed claims. Recurves are more forgiving but still benefit from a clean anchor and consistent draw.
When the rule breaks down
The wingspan formula assumes proportional limbs and a normal anchor. If your arms are unusually short for your height, or you anchor far back along your jaw, your real draw length may be ½ to 1 inch off the rule of thumb. A draw board check at a pro shop is the gold standard for any archer serious about scoring.