Held horizontal, or left alone

An erection at its natural angle often points up rather than straight out, which makes a ruler awkward to hold level against it. The tempting fix is to press the shaft down to horizontal before reading. That fix changes the number.

What pressing down actually does

Pushing an upward-angled shaft down toward horizontal does two things at once, and both work against an accurate reading. It compresses the base against the pubic bone from a different direction than the bone-pressed technique assumes, which can shift where the fat pad sits relative to the ruler and change how much it compresses. And it can shift where the base landmark itself sits, because the point the shaft pivots from is not perfectly fixed - forcing an angle it does not naturally hold moves tissue around that pivot in a way a relaxed reading does not.

The result is a reading that is not quite the bone-pressed, natural-angle length the method calls for, and not quite anything else with a name, either. It is close, which is exactly the problem: close enough to look right and off by an amount nobody can put a figure on.

The alternative: read along the axis

The fix is to keep the ruler along whatever axis the shaft is actually pointing at, rather than forcing the shaft to match a horizontal ruler. This is a different point from keeping the ruler parallel to the shaft rather than tilted relative to it, which is about the ruler tracking whatever angle the shaft holds. This is about not moving the shaft's angle in the first place. In practice that usually means reading at an angle rather than level, which is harder to do standing over yourself and easier with a squarer view, sighted properly rather than looking down and forward at a ruler pointing up and away.

Why the intuition is backwards

The instinct to press down to horizontal usually comes from wanting to make the ruler easier to hold level, which feels like it should produce a cleaner reading rather than a worse one. The problem is that "easier to hold" and "accurate" are answering different questions here. A ruler held level is genuinely easier to read without parallax, but that convenience is bought by moving the thing being measured, not the instrument doing the measuring - and the whole point of a fixed protocol is that the anatomy stays where it naturally sits while the instrument adapts to it, not the other way round. The same trade-off shows up, in a different form, in why a tape used for length reads long: both are cases where making the physical act of measuring more comfortable costs accuracy, because the convenience comes from changing the thing being measured rather than the tool.

Record the choice either way

If pressing to horizontal genuinely is the only workable option for a given reading, it is not disqualifying, but it belongs in the method line next to the figure - "pressed to horizontal" is a real caveat, the same way "supine" or "non-bone-pressed" is, and it tells a future reader, including your future self, that the number carries an extra source of error the natural-angle version does not.

What this is not about

This is a mechanics-of-the-ruler question, nothing more. It has no bearing on how an erection's angle looks or reads to another person, which is a subjective, photograph-dependent question that other sites are built around - a scoring service like Rate Cock evaluates a submitted photo as a whole, and what framing and angle contribute to a photo score is a question for that kind of tool, not a ruler. A human reviewer looking at the same photo forms an impression the same way, and Rate Penis's judges are explicit that it's an impression rather than a measurement. An AI model asked to estimate anything from a photo is working from what it can infer about the image rather than resolving an axis the way a ruler does, which AI Penis explains is a question of what a model can see, not what it can compute.

The short version

Let the shaft point where it points, run the ruler along that same line, and if you have to compromise, write down that you did.