⚠️ MEDICAL DISCLAIMER: This calculator is for EDUCATIONAL purposes only. Prostate volume and PSA density are screening tools, not diagnoses. Always consult a urologist for interpretation and treatment decisions.
🩺 Prostate Volume (cc) = Length × Width × Height × 0.5236 (π/6). Example: 4.0 × 5.0 × 3.5 × 0.5236 = 36.6 cc. Normal: 20-30 cc. Over 40 cc = BPH. PSA Density = PSA ÷ Volume. Under 0.15 = reassuring. Enter your dimensions below for exact volume — free, no signup.
⚠️ Educational estimate only. Actual volume may differ by 10-15% from ellipsoid formula. Confirm with urologist.
📋 Key Takeaways — Prostate Volume at a Glance
Formula: Volume (cc) = L × W × H × 0.5236 (π/6)
Normal adult prostate: 20-30 cc (walnut size)
30-40 cc: Mildly enlarged
40-80 cc: Moderate BPH (treatment considered)
80+ cc: Severe BPH
PSA density under 0.15 = reassuring
Prostate grows 1-2 cc per year after age 40
ℹ️ This free prostate volume calculator uses the standard ellipsoid formula (L × W × H × 0.5236). Enter dimensions from your ultrasound or MRI report to get exact volume in cc and PSA density. Updated November 2026.
📊 Formula: Volume (cc) = L × W × H × 0.5236 | PSA Density = PSA (ng/mL) ÷ Volume (cc) | Normal: 20-30 cc | BPH: over 40 cc
💡 Note: Benign prostate growth (BPH) raises PSA by ~0.1 ng/mL per 10 cc. PSA density corrects for this — it's more useful than raw PSA alone.
📊 Prostate Volume by Age (Normal Range)
Age
Normal Volume
Notes
20-30
20-25 cc
Baseline adult size
30-40
25-30 cc
Slow growth begins
40-50
30-35 cc
Growth ~1-2 cc/year
50-60
35-40 cc
Symptoms may start
60-70
40-45 cc
BPH common
70+
45-50+ cc
Treatment often considered
📊 Prostate Size Categories
Volume
Category
What It Means
Under 30 cc
Normal
Healthy prostate size
30-40 cc
Mildly Enlarged
Symptoms may begin
40-80 cc
Moderate BPH
Treatment often considered
80+ cc
Severe BPH
May need surgery
📊 PSA Density Interpretation
PSA Density
Interpretation
Recommended Action
Under 0.10
Very reassuring
Routine monitoring
0.10-0.15
Reassuring
Repeat PSA in 6-12 months
0.15-0.20
Borderline
Consider biopsy if PSA elevated
Over 0.20
Elevated risk
Urologist referral, biopsy discussion
👨 Robert, 58 — BPH Diagnosis
Measurements: 4.5 × 5.2 × 3.8 cm | PSA 4.8 ng/mL
Result: Volume = 46.5 cc (Moderate BPH) | PSA density = 0.10 (reassuring)
✅ "Volume was enlarged but PSA density was normal — just BPH, no biopsy needed."
👨 Michael, 65 — Elevated PSA
Measurements: 4.0 × 4.5 × 3.5 cm | PSA 8.0 ng/mL
Result: Volume = 33.0 cc (Mildly enlarged) | PSA density = 0.24 (elevated risk)
⚠️ "Small prostate with high PSA = elevated density. Doctor recommended biopsy."
The 0.5236 is π/6 — the mathematical constant for the volume of an ellipsoid.
Example: Length 4.0 cm × Width 5.0 cm × Height 3.5 cm × 0.5236 = 36.6 cc.
What is a Prostate Volume Calculator?
A prostate volume calculator converts three ultrasound or MRI measurements into prostate size in cubic centimeters (cc). It also calculates PSA density — a more useful screening metric than raw PSA alone.
How does it work? Enter the AP (length), LR (width), and SI (height) measurements from your imaging report. The calculator applies the ellipsoid formula and instantly shows volume, size category, normal range for your age, and PSA density.
What is Normal Prostate Size?
The normal adult prostate is 20-30 cc — about the size of a walnut. It grows slowly with age:
Age 20-30: 20-25 cc
Age 40-50: 30-35 cc
Age 60-70: 40-45 cc
Age 70+: 45-50+ cc
Over 40 cc is considered enlarged (BPH). Over 80 cc is severe. Symptoms often start at 30-40 cc.
What is PSA Density?
PSA Density = PSA (ng/mL) ÷ Prostate Volume (cc).
It corrects for the fact that larger prostates produce more PSA. A high PSA with a large prostate may be benign. A high PSA with a small prostate is more concerning.
Under 0.15: Reassuring — likely BPH, not cancer
0.15-0.20: Borderline — consider biopsy if PSA elevated
Over 0.20: Elevated risk — urologist referral
How is Prostate Volume Measured?
Three methods:
Transrectal ultrasound (TRUS): Most common. Measured in 3 dimensions. 85-90% accurate.
MRI: Most accurate. Used before biopsy or surgery planning.
DRE (digital rectal exam): Rough estimate only. Not precise enough for volume.
Your ultrasound or MRI report will show Length, Width, and Height in cm. Enter those values above.
What is BPH?
Benign Prostatic Hyperplasia (BPH) is non-cancerous prostate enlargement. It affects 50% of men by age 50, and 80% by age 80. Symptoms:
Frequent urination (especially at night)
Weak urine stream
Urgency and hesitancy
Incomplete bladder emptying
Treatment starts with lifestyle changes, then medications (alpha-blockers, 5-alpha reductase inhibitors), then surgery (TURP, laser) for severe cases.
Why Use Our Prostate Volume Calculator?
Our free prostate volume calculator is built for accuracy and privacy. It runs entirely in your browser — no data is stored, no sign-up required. It uses the same ellipsoid formula as urologists worldwide. Whether you're reviewing your ultrasound report or preparing for a urology appointment, our tool delivers clear results in seconds.
❓ Frequently Asked Questions
How do you calculate prostate volume?
Prostate Volume (cc) = Length × Width × Height × 0.5236 (π/6). Example: 4.0 cm × 5.0 cm × 3.5 cm × 0.5236 = 36.6 cc. This is the standard ellipsoid formula used by urologists worldwide.
What is a normal prostate size?
Normal adult prostate is 20-30 cc (about the size of a walnut). At age 20-30: 20-25 cc. At age 40-50: 25-30 cc. At age 60+: 30-40 cc is common. Over 40 cc is considered enlarged (BPH). Over 80 cc is severe.
What is PSA density?
PSA Density = PSA (ng/mL) ÷ Prostate Volume (cc). It helps distinguish BPH from prostate cancer. Density under 0.15 is reassuring. 0.15-0.20 is borderline. Over 0.20 warrants biopsy consideration, especially with elevated PSA.
What is considered an enlarged prostate (BPH)?
Prostate over 30 cc is mildly enlarged. Over 40 cc is moderate BPH. Over 80 cc is severe BPH. Symptoms like frequent urination, weak stream, and nocturia usually start at 30-40 cc. Treatment is considered at 40+ cc with symptoms.
How is prostate volume measured?
Three methods: 1) Transrectal ultrasound (TRUS) — most common, measured in 3 dimensions. 2) MRI — most accurate, used before biopsy. 3) DRE (digital rectal exam) — rough estimate only. Ultrasound or MRI reports give L, W, H in cm that you enter here.
What is a normal PSA level?
PSA under 4.0 ng/mL is generally normal. 4.0-10.0 is the gray zone (biopsy consideration). Over 10.0 has high cancer risk. But PSA rises with age and prostate size, so PSA density is more useful than raw PSA alone.
What size prostate causes symptoms?
Symptoms (frequent urination, weak stream, urgency) usually start at 30-40 cc. Larger prostates (60-80+ cc) cause more severe symptoms and may require surgery. Some men with small prostates have severe symptoms due to location of enlargement.
What is the formula for PSA density?
PSA Density = Total PSA (ng/mL) ÷ Prostate Volume (cc). Example: PSA 4.0 ÷ Volume 40 cc = 0.10 ng/mL/cc (reassuring). PSA 6.0 ÷ Volume 30 cc = 0.20 (borderline, consider biopsy).
Does prostate size affect PSA levels?
Yes. Benign prostate growth (BPH) raises PSA by about 0.1 ng/mL per 10 cc of prostate tissue. A 60 cc prostate may have PSA of 5-6 ng/mL from BPH alone. PSA density corrects for this.
What is a normal prostate volume by age?
Age 20-30: 20-25 cc. Age 30-40: 25-30 cc. Age 40-50: 30-35 cc. Age 50-60: 35-40 cc. Age 60-70: 40-45 cc. Age 70+: 45-50+ cc. Prostate grows about 1-2 cc per year after age 40.
Can prostate volume shrink?
Yes, with medication. 5-alpha reductase inhibitors (finasteride, dutasteride) shrink the prostate 20-30% over 6-12 months. This also lowers PSA by ~50%. Surgery (TURP) removes tissue and reduces volume permanently.
How accurate is the prostate volume calculator?
The ellipsoid formula (L × W × H × 0.5236) is about 85-90% accurate compared to actual specimen weight. TRUS measurements are slightly less accurate than MRI. Actual prostate weight may differ by 10-15% due to shape irregularities.
💡 Expert Tips for Prostate Volume
Tip #1: Always use measurements from the same imaging method (ultrasound or MRI). Mixing methods gives inconsistent results.
Tip #2: PSA density is more useful than raw PSA alone — especially when PSA is in the 4-10 gray zone.
Tip #3: A small prostate with high PSA (elevated density) is more concerning than a large prostate with high PSA (normal density).
Tip #4: 5-alpha reductase inhibitors (finasteride) shrink the prostate 20-30% and lower PSA by ~50%. Account for this when interpreting PSA.
Tip #5: Repeat imaging every 1-2 years for BPH monitoring. Sudden prostate growth warrants evaluation.
Tip #6: Never use this calculator alone for cancer screening. Combine with DRE, PSA trend, and urologist evaluation.
🩺 Still Asking "What's My Prostate Volume?"
Enter dimensions. Get exact volume and PSA density in 30 seconds. Free, no signup.
🛡️ CDCalculators prostate volume calculator — data sources: Standard ellipsoid formula, AUA BPH guidelines, NCCN prostate cancer guidelines. Last updated November 12, 2026. Disclaimer: Educational estimate only. Confirm with urologist.