Arrow FOC Calculator
Calculate your arrow's Front-of-Center for optimal archery performance
Calculate Arrow FOC
Full length of the arrow from nock to point
Distance from throat of nock to balance point
Example: Hunting Arrow FOC
Arrow Specifications
Arrow Type: Carbon hunting arrow
Total Length (A): 30 cm (11.8 inches)
Balance Point (B): 18 cm (7.1 inches)
FOC Calculation
Step 1: Center point = 30 ÷ 2 = 15 cm
Step 2: Deviation = 18 - 15 = 3 cm forward
Step 3: FOC = (3 ÷ 30) × 100 = 10%
Result Analysis
This 10% FOC is optimal for hunting applications, providing excellent balance between speed, accuracy, and penetration power.
Benefits of Proper FOC
Better Accuracy
Improved flight stability and grouping
Deeper Penetration
Better energy transfer on impact
Wind Resistance
Improved performance in crosswinds
Consistent Flight
More predictable arrow behavior
How to Adjust FOC
Increase FOC
- • Use heavier broadheads/points
- • Add weight inserts
- • Use lighter nocks/fletching
- • Trim arrow from nock end
Decrease FOC
- • Use lighter points
- • Add weight to nock end
- • Use heavier fletching
- • Trim arrow from point end
Understanding Arrow FOC (Front-of-Center)
What is Arrow FOC?
Arrow FOC (Front-of-Center) is a measurement that indicates how far forward the balance point of an arrow is from its physical center. It's expressed as a percentage and is crucial for arrow performance, stability, and accuracy.
Why FOC Matters
- •Higher FOC improves arrow stability during flight
- •Proper FOC enhances penetration power
- •Optimal FOC reduces wind drift
- •Correct FOC improves grouping consistency
FOC Formula Explained
FOC = ((B - A/2) / A) × 100
A: Total arrow length
B: Distance from nock to balance point
A/2: Physical center of the arrow
Finding Balance Point
- 1. Place arrow on a thin edge (knife, ruler)
- 2. Slide until arrow balances horizontally
- 3. Mark the balance point
- 4. Measure from nock throat to balance point
Archery Applications
Target Archery
8-12% FOC
Balance of speed and accuracy
Hunting
10-15% FOC
Optimal penetration power
3D Competition
6-10% FOC
Speed for unknown distances