OZ FISH & GAME · HUNTING RESOURCES
Arrow Speed Calculator
Estimate your arrow’s speed, kinetic energy and momentum using your bow specifications and arrow weight. If you have a chronograph reading, enter it for more accurate results.
Bow & Arrow Setup
Your bow's advertised IBO speed.
Include the shaft, point, insert, nock and fletching.
Combined weight of peep sights, silencers and other accessories. Enter 0 if none.
Enter your chronograph reading to calculate kinetic energy and momentum using measured speed.
Your Results
Estimated speedEnergy and momentum are calculated at launch using the estimated or measured arrow speed.
Understanding Your Results
Faster arrows reach the target sooner and follow a flatter trajectory, reducing the amount of drop over a given distance.
Kinetic energy is the energy an arrow carries in flight. It increases with arrow weight and rises significantly with speed. While useful for comparing arrow setups, kinetic energy alone doesn’t determine penetration.
Momentum is calculated from the arrow’s mass and speed. Heavier arrows can have greater momentum despite travelling more slowly. This makes momentum a useful measure when comparing different arrow setups.
How the Calculator Works
The calculator estimates arrow speed using your bow’s advertised IBO rating, adjusted for draw weight, draw length, arrow weight and string accessories.
These estimates provide a useful starting point for comparing different setups. Actual speeds vary depending on the bow, its tuning and other factors.
If you have a chronograph reading, enter it to calculate kinetic energy and momentum using your measured speed instead.
Speed estimate: IBO speed − 2 × (70 − draw weight in lb) − 10 × (30 − draw length in inches) − (arrow weight in grains − 350) ÷ 3 − string accessory weight in grains ÷ 3.
Kinetic energy (ft-lb): arrow weight (grains) × speed² (fps) ÷ 450,240. Momentum (slug-ft/s): arrow weight (grains) × speed (fps) ÷ approximately 225,218.
Conversions: 1 ft-lb ≈ 1.35582 joules; 1 slug-ft/s ≈ 4.44822 kg·m/s; 1 fps = 1.09728 km/h. Results are calculated at launch, not at the target. Arrow penetration also depends on broadhead design, arrow flight and impact conditions.