Bow Size Calculator

Guide

The Math, the Chart & How to Measure

💡 Quick Summary

Core Insight: Arm span ÷ 2.5 = draw length, and draw length is what actually sizes a recurve or longbow (62″–72″ for most adults, shorter takedown lengths for youth). A compound's size question is different — its draw comes from the cam module, so axle-to-axle is really a hunting-vs-target tradeoff, not a draw-length lookup.

Ideal For: Picking a first bow length before a shop visit, sanity-checking a size a shop already recommended, or fitting a bow for a youth archer whose numbers change every season.

How Do You Measure Arm Span for Bow Sizing?

Stand square to a wall, arms stretched straight out to the sides at shoulder height, palms flat against the wall or a door frame.

Mark both fingertips and measure the straight-line distance between the marks — not the shoulder-to-shoulder width, and not a diagonal.

Divide by 2.5. A 66″ arm span gives a 26.4″ draw length — the same wingspan-over-2.5 method this site's Draw Length Calculator runs on, reused here as the first step toward a bow size.

Quick Bow Length Reference Table

The adult bands above follow the standard AMO draw-length-to-bow-length convention, cross-checked against Archery Care's recurve sizing guide: bow length follows draw length, not height or arm strength, because a mismatched pairing either wastes the limbs' working range (bow too long) or sharpens the string angle enough to pinch tab fingers at anchor (bow too short). The under-25″ rows use commonly stocked youth and compact takedown lengths rather than a single adult number, since a 62″ recurve is unwieldy for most archers drawing under two feet.

Why Doesn't Draw Length Size a Compound the Same Way?

A recurve or longbow's limbs are built around one draw length. A compound's cam module sets the draw instead, so the riser can run any axle-to-axle length regardless of how far you pull. Nock On Archery's own axle-to-axle explainer frames it as a tradeoff, not a formula: a shorter ATA bow is easier to maneuver in a treestand, a ground blind or thick cover, while a longer one gives a steadier hold and a more forgiving string angle at full draw — and that gap gets more noticeable the longer your own draw length runs.

⚠️ Field Notes: Sizing Between Two Numbers

Landed between two bow lengths on the table above? Size up, not down. A slightly long recurve costs a little smoothness and stack; a slightly short one sharpens the string angle at your anchor and pinches your fingers or D-loop more than most beginners expect. The most common mistake this calculator sees isn't the math — it's archers chasing a maximum draw weight before their form is settled, which is exactly backwards for building a repeatable shot.

🗣️ Community Consensus & Synthesis Grid

Reddit/Discord Sentiment: Aggregated from recurring bow-fit threads on r/Archery and ArcheryTalk's technical forum, the arm-span-over-2.5 starting point is treated as reliable, with a full-draw check at a shop recommended before a final purchase — especially for a takedown recurve, where swapping limb length later is possible but swapping riser length is not.

Top Praised Point: Threads consistently favor sizing a beginner recurve slightly long over slightly short, for exactly the string-angle reason in the field note above.

Common Friction Point: New compound shooters report being sold on axle-to-axle length as if it were a draw-length lookup the way a recurve is, then finding out later it was actually a maneuverability-versus-stability choice the shop never explained.

Frequently Asked Questions