1. Input Parameters
3.00 mL
WHO gravimetric standard: 1.0 g weight = 1.0 mL volume (excluding container).
30 yr
Accounts for accessory gland involution (inflection at age 45 yr).
4.0 d (96 hr)
✓ Within the official WHO 2 to 7 day pre-analytical standard
window.
WHO 6th Exact Empirical Knots (at Age 30, Day 4):
Active
2. Statistical & Clinical Classification
Normospermia (Typical Range)Adjusted Percentile
50.0%
WHO Raw: 50.0%
Z-Score (Normal Eq.)
+0.00 σ
Mean Δ: -0.35 mL
Rarity / Frequency
1 in 2
at or above median
Expected Mean ± SD
3.35 ± 1.52
CV: 45.4%
Adjusted Reference Centiles for Selected Inputs (mL)
Gamma(α=4.86, β=0.69)
P2.5
1.00
P5 (Low)
1.40
P10
1.80
P25
2.30
P50 (Med)
3.00
P75
4.20
P90
5.50
P95 (High)
6.20
P97.5
6.90
Model Scaling Multipliers:
f_age =
1.000 ×
f_abs =
1.000 →
Combined =
1.000x
3. Right-Skewed Gamma Probability Density (PDF) & Cumulative Percentile (CDF)
Shaded red zone (< 1.4 mL) marks WHO 6th Edition hypospermia; orange zone (> 6.2 mL) marks 95th centile hyperspermia.
Adjusted Cohort PDF
Cumulative Percentile (CDF %)
All parameters above are compiled ahead of time from peer-reviewed clinical literature. See the Datasets & Methodology page for the cited clinical literature and statistical methodology.