Free PSA (%)
Free PSA percentage is the ratio of free (unbound) PSA to total PSA in the blood. It helps distinguish between prostate cancer and benign prostate conditions when total PSA is mildly elevated.
Category: Tumor Markers
Also known as: free psa, free psa %, % free psa, psa free, free psa percent, psa free percent, free/total psa
Reference range: 25–100 % (Source: ABIM)
Standard unit: %
High values may indicate
A high free PSA percentage (above 25%) suggests the PSA elevation is more likely due to benign prostatic hyperplasia (BPH) rather than cancer.
Low values may indicate
A low free PSA percentage (below 10%) suggests a higher probability of prostate cancer, and further evaluation such as a prostate biopsy may be recommended.
Frequently asked questions
- What is a normal Free PSA (%) level?
- A typical reference range for Free PSA (%) is 25–100 % (source: ABIM). Reference ranges vary by laboratory, age, and sex, so always compare against the range on your own lab report.
- What units is Free PSA (%) measured in?
- Free PSA (%) is most commonly reported in %. Labs in different countries may use other units — you can convert between them with BloodId's blood test unit converter.
- Where do Free PSA (%) reference ranges come from?
- BloodId uses ABIM standard reference ranges and educational information from MedlinePlus (see our methodology). Reference ranges still vary by lab, age, and sex, so always compare against your own report.
- Can I track Free PSA (%) over time?
- Yes. Upload results from any lab and BloodId charts your Free PSA (%) over time against its reference range, so you can see whether the trend is rising, falling, or stable.
Related biomarkers
Source: MedlinePlus, U.S. National Library of Medicine
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