What is a good FOC for hunting arrows?

For hunting, most experienced archers recommend 10–15% FOC for general use, or 13–19% for large/dangerous game where penetration is critical. The ideal balance gives stable flight and good penetration without excessive arc. Standard broadhead setups with 100-grain tips on a 28-inch arrow typically fall in the 11–14% range naturally.

How do I measure the balance point of my arrow?

Balance the complete arrow (with nock, fletching, insert, and point installed) horizontally on a narrow pivot — a pencil point is ideal. Mark the exact spot where it balances without tipping. Measure from the nock groove (the deepest point of the nock slot) to that mark. This is your balance point distance (A) used in the FOC formula.

Does FOC matter for target archery?

Yes, but less critically than for hunting. Target archery typically uses 7–12% FOC — enough for stable flight without excessive drop. Outdoor field archery at long ranges (60–90 meters) benefits from slightly lower FOC for flatter trajectory. Indoor target at short ranges (18m) can use higher FOC without trajectory penalty.

How does point weight change FOC?

Heavier points (broadheads or field tips) significantly increase FOC. Moving from 75-grain to 125-grain points on an average arrow can shift FOC from 11% to 16% or more. This is why hunters often test FOC with their actual broadheads installed — swapping field points for broadheads during season changes your arrow's balance and flight characteristics.

How to Calculate Arrow FOC: Front of Center Balance for Accuracy

Understand how Arrow Front of Center (FOC) balance affects arrow flight, how to calculate your FOC percentage, and what percentage range gives best accuracy for hunting or target archery.

Related Calculators

FOC Calculator
Calculate an arrow’s front-of-center balance percentage from finished arrow length and balance-point distance measured from the nock throat.

What Is Arrow FOC?

FOC — Front of Center — is a measure of where the balance point of an arrow falls relative to the arrow's center, expressed as a percentage. It describes how much of the arrow's weight is concentrated in the front half.

A higher FOC means more weight forward, which creates a more stable, nose-forward flight trajectory but less flat trajectory at long ranges.

The FOC Formula

FOC (%) = ((Balance Point from Nock End − Arrow Length / 2) / Arrow Length) × 100

More precisely using the standard AMO/ATA formula: FOC (%) = ((A − L/2) / L) × 100

Where: - A = distance from nock groove to balance point (in inches or mm) - L = overall arrow length (nock groove to end of shaft, not including tip)

Important: Measure from the nock groove (the deepest point of the nock slot where the string rests), not the back end of the shaft.

Step-by-Step Calculation

Example arrow: - Total length: 28 inches (nock groove to shaft end) - Balance point from nock groove: 17.5 inches

Step 1: Find arrow center: L/2 = 28 / 2 = 14 inches

Step 2: Distance past center: 17.5 − 14 = 3.5 inches forward of center

Step 3: FOC % = (3.5 / 28) × 100 = 12.5% FOC

How to Find Your Balance Point

Install all arrow components: nock, fletching, insert, and point (hunting broadhead or field point)
Balance the arrow horizontally on a small pivot (a pencil point works)
Mark where the arrow balances
Measure from the nock groove to that mark

The balance point will shift when you change point weight — heavier points push FOC higher; lighter points reduce FOC.

Optimal FOC Ranges

Use Case	Recommended FOC
3D target archery	7–11%
Field archery / long range	9–13%
Hunting (general)	10–15%
Big game hunting	13–19%
Extreme FOC for penetration	19–30%+

Standard archery: Most organizations (NFAA, World Archery) recommend 10–15% for broadhead hunting. Too low FOC (<7%) causes instability; excessive FOC (>25%) hurts trajectory.

How FOC Affects Arrow Flight

Higher FOC: - More stable flight (resists wind drift) - Better penetration on game (nose dives in) - More pronounced arrow drop at longer distances

Lower FOC: - Flatter trajectory (better for long range) - Less stable — requires perfect form and tuning - Faster forgiveness of slight releases

Adjusting FOC

To increase FOC: - Add weight to the tip (heavier broadhead or field point) - Use lighter fletching - Use lighter nock

To decrease FOC: - Switch to lighter broadhead or field point - Add weight to the rear (heavier nock, heavier fletching)

Frequently Asked Questions

What is a good FOC for hunting arrows?: For hunting, most experienced archers recommend 10–15% FOC for general use, or 13–19% for large/dangerous game where penetration is critical. The ideal balance gives stable flight and good penetration without excessive arc. Standard broadhead setups with 100-grain tips on a 28-inch arrow typically fall in the 11–14% range naturally.
How do I measure the balance point of my arrow?: Balance the complete arrow (with nock, fletching, insert, and point installed) horizontally on a narrow pivot — a pencil point is ideal. Mark the exact spot where it balances without tipping. Measure from the nock groove (the deepest point of the nock slot) to that mark. This is your balance point distance (A) used in the FOC formula.
Does FOC matter for target archery?: Yes, but less critically than for hunting. Target archery typically uses 7–12% FOC — enough for stable flight without excessive drop. Outdoor field archery at long ranges (60–90 meters) benefits from slightly lower FOC for flatter trajectory. Indoor target at short ranges (18m) can use higher FOC without trajectory penalty.
How does point weight change FOC?: Heavier points (broadheads or field tips) significantly increase FOC. Moving from 75-grain to 125-grain points on an average arrow can shift FOC from 11% to 16% or more. This is why hunters often test FOC with their actual broadheads installed — swapping field points for broadheads during season changes your arrow's balance and flight characteristics.

Last updated 7/28/2026