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Compound bows are rated at a specific draw length (typically 28 or 30 inches). Weight increases or decreases ~2.5 lb per inch from rated length on most compounds.
Weight at DL = rated weight + (your DL − rated DL) × 2.5 lb/inCompound bows have peak weight at full draw with let-off reducing holding weight. Listed weight is peak weight before let-off (e.g., 70 lb peak, 85% let-off = 10.5 lb hold).
Hold weight = peak weight × (1 − let-off%)Recurves follow similar ~2 lb per inch rule from rated length. Longer draw = higher weight; shorter draw = lower. Measured on scale is most accurate.
Recurve: ~2 lb/in change from rated draw lengthUpdated: July 2026
Shorter draw: 70 − (2 × 2.5) = 65 lb peak weight. With 80% let-off, holding weight = 65 × 0.20 = 13 lb at full draw.
Longer draw: 60 + (2 × 2.5) = 65 lb peak. Verify does not exceed bow's max limb weight rating before adjusting draw module.
Shooter with 29-inch draw: approximately 42 lb on scale. Finger tab vs release does not change limb weight — only how it feels at full draw.
A "70 lb" bow is 70 lb at its rated draw length only. Measure at your draw length — a 70 lb@30 bow at 27 inches draws ~62 lb.
Arrow spine selection uses peak draw weight, not let-off holding weight. A 70 lb compound with 85% let-off still needs arrows spined for 70 lb peak.
Bow draw weight varies with draw length — a bow marked 70 lb is rated at a specific AMO draw length. This calculator determines your actual draw weight at your draw length for compound and recurve bows.