🦍 Ape Index Calculator
Discover how your arm span compares to your height and what that means for performance in reach-dependent sports.
Ape Index Difference
4.0 cm
Wingspan − Height
Ape Index Ratio
1.022
Wingspan ÷ Height
Classification
Advantageous (+4 to +7 cm)
Higher ratios favor reach-intensive sports
How to Use This Calculator
Select units
Choose metric (cm) or imperial (inches) for measurements.
Measure height
Stand against a wall without shoes; measure from floor to crown.
Measure wingspan
Extend arms horizontally; measure fingertip to fingertip.
Review classification
Compare your difference and ratio to evaluate reach advantage.
Formula
Ape Index = Wingspan − Height
Ape Index Ratio = Wingspan ÷ Height
A positive difference signals a longer reach relative to height, commonly seen in climbers, basketball players, and swimmers. The ratio normalizes proportions for easy comparison across body sizes.
Example
Height 178 cm, wingspan 184 cm → Difference = +6 cm, Ratio = 1.034. Classification: Advantageous.
Variables
- Height: Standing height
- Wingspan: Fingertip-to-fingertip reach
- Difference: Reach advantage in length units
- Ratio: Proportion for cross-sport comparisons
Understanding Ape Index
Ape index highlights limb-length advantages. Sports that favor extended reach—rock climbing, Brazilian jiu-jitsu, boxing, swimming—often correlate higher performance with positive ape indices.
Sport-Specific Insights
- Climbing: Longer reach aids holds and reduces dynos.
- Basketball: Wingspan influences defensive coverage and shot blocking.
- Combat Sports: Extended reach controls distance in striking and grappling.
- Swimming: Longer arms improve stroke length.
Keep in Mind
- Strength, technique, and flexibility matter as much as limb length.
- Negative ape index athletes can excel with refined movement and explosive power.
- Use the ratio to track growth changes for juniors or compare athletes across teams.
Frequently Asked Questions
How accurate are home measurements?
Use a wall, tape measure, and helper for best results. Repeat measurements to ensure consistency.
Is a negative ape index bad?
No. Many successful athletes have neutral or negative indices. Focus on training strengths.
Do growth spurts change ape index?
Yes, especially in teenagers. Track periodically to observe body proportion changes.
What about leg length?
This calculator focuses on arm span vs height. Leg length influences stride length separately.
Can I compare metric and imperial?
Results display in your chosen units; ratios are unitless, so they compare universally.