Why do I seem to be between the answers on the Tanner Stage Calculator?

Last updated on August 28, 2020

Question:

I found your web site online and saw the Tanner chart and took the quiz. I got my results, but it doesn’t really seem to define me.  I am getting kind of worried because it seems boys in my school look a lot more mature than I do. Am I normal? I’ll copy the format of the boy I saw online

I am 15 years old. I have relatively average hands for most boys my height (5’10”) and my feet size is 11-11.5. My voice is deeper than when I was a kid, but it still cracks. I have no hair on my chest, other than a few hairs around my nipples.  Some hair is beginning to grow around my belly button.  I have a few dark hairs on my face and a few under my chin. I shave every 8-10 days.  My penis is about 2.5 inches when flaccid and about 5 inches when erect.  My testicles are about longer than an inch on the long axis. I am fairly strong, but it may be because I work out and play football. I don’t look as strong as boys who look older than me, but I often can lift more weight than they can.  The reason the Tanner scale wasn’t right is that I do have pubic hair that is thick and curly, but it does not grow toward my naval.  For almost every question it seemed like I fell somewhere in between of fulfilled multiple answers. If you can help me it would really be great.

Answer:

I would expect most people to fall between the descriptions. Change is continuous. For example, in the picture to the right, we can say that A is blue and C is green, but where does B fall between those two points? Is it blue or green? For the same reason, I can write descriptions of the major points of change, but I can’t cover all the subtle small changes in between. It is part of the reason there are multiple questions dealing with several ways the Tanner stages can be measured. When you pick what you think is the closest fit, the calculator gives you an estimate of where you are in your development. The Tanner scale is actually only five numbers from 1 to 5. I added in a decimal point to give a better feel for progress made within a stage.

You describe yourself as someone in the middle of stage 4. That means most of your vertical height has been reached, though you will probably put on another inch or so before the end.