Bone-Pressed vs Non-Bone-Pressed Measurement (BPEL vs NBPEL)
Bone-pressed erect length (BPEL) is the gold standard used in clinical research, where the ruler is pushed firmly past the lower belly fat pad until it rests directly against the hard pubic bone. Non-bone-pressed erect length (NBPEL) simply measures the visible portion of the shaft from the skin surface, leaving the fat pad uncompressed. Depending on your body fat percentage and genetics, the pubic fat pad typically conceals between 0.5 and 1.5 inches (1.3 to 3.8 cm) of your true anatomical length. Because all scientific averages (including the 5.16-inch benchmark) are reported as BPEL, you must bone-press to get an accurate comparison.
Why doctors exclusively use BPEL
If researchers used NBPEL, an identical penis would measure 5.5 inches when the subject is lean, but drop to 4.2 inches if he gained 30 pounds. Compressing to the pubic bone neutralizes the effect of body fat and measures the true skeletal attachment point.
How hard should you push the ruler?
Press gently but firmly until you feel the resistance of the solid pelvic bone. It should never be painful or cause bruising, but it should firmly compress the soft cushion of fatty tissue in front of the bone.
Which number matters during sex?
Both matter in different ways: NBPEL is what you see when you look down, and what your partner sees visually. BPEL is what can actually enter during penetration, because the soft pubic fat pad naturally compresses against your partner's pelvis during intercourse.
My Size Report provides a private, calculator-led way to understand measurements against published research. Results are informational and should not be treated as medical advice.