Why do I appear to be in one stage in some things and another stage in other things?

Last updated on February 3, 2022


This question has been stuck in my mind for quite a while, and I want to be positive I have a clear answer. I don’t completely trust the calculator, and I am begging for a human answer. What stage am I in?

I am 12 years old. At the beginning of the school year, I noticed I had pubic hair growing around my penis. I also noticed some hair on the upper lip. In November, I noticed that my voice was cracking sometimes. Later I also noticed that my pubic hair was getting a little bit darker, and was starting to get a little curly. I would assume instantly that I would be in stage 3 from that, but when I look at the pubic hair picture for stage 3, it looks more filled and covering over more.

I also have noticed my scrotum hanging down. A lot of the time the left testicle hangs lower than the right. But when my scrotum isn’t hanging, both testicles seem to be at the same height. I also noticed that my penis seems to be getting longer.

My parents started to comment on me getting taller. People also comment on my “mustache.” It says that in stage 3 you should have armpit hair, but I don’t see any growth at all. I want to hope I am in stage 3, but sometimes I feel like I am probably only in stage 2. If I do happen to be in stage 3, how long do you think it will take to get to stage 4? I really want to get there, and it seems like I am going through puberty faster than most people, but I’m not sure.

Thank you so much, and please respond.


Please understand that I’m working from second-hand information. I only know what you tell me. I can’t double-check whether your observations are correct or not. What I typically recommend is that you see a doctor because he can see you and, therefore, can give you a more accurate assessment.

Most people want to think in fixed steps, but growth is a continuous progression of change. The descriptions and images used in the calculator are trying to capture fixed points in that progression of change. For example, the pubic hair illustrations are for a boy at about three-quarters of the way through that particular stage. Since the stages are about two years in length, the picture represents a boy who has been in that stage for about 18 months.

One of the difficulties in measuring progress is that there are numerous systems that are semi-independently developing. Within a system, the order is fixed, but between systems, there can be variance. For example, the development of facial hair goes in this order:

  1. Upper lip
  2. Chin
  3. Sideburns
  4. Jaw line
  5. Cheeks

The hair darkens on the upper lip in stage 3 — most of the time. For some boys, it might appear in late stage 3. For others, especially those who don’t get facial hair, the few hairs they do get might not appear until stage 5.

Pubic hair goes in this order:

  1. The base of the penis
  2. Spreading outward across the groin
  3. Filling in thicker
  4. A strip of hair going up to the belly button
  5. Hair covering the inside thighs

Pubic hair starts showing up in stage 2.

What the calculator does is ask about all of the systems to get your idea of your progress. Sometimes the questions are asked in different ways to double-check the accuracy of your observations. Then a weighted average of each system is combined to give an estimate of where you are at.

From your description, you are in the early part of stage 3. The armpit hair will come later in stage 3. It develops during stage 3, but it isn’t necessarily there at the start of stage 3. Stage 3 officially is when your rate of growth is greater than 2 inches per year. The longer you are in stage 3, the taller you will be in the end, so don’t be in a great hurry. Not that you can change the rate of change. Most stages last about two years in boys. Stage 3 is the stage with the most dramatic changes, so that is why it seems you are developing quickly.

Even given the fact that the calculator is dependent on your observations, it tends to be fairly accurate in its assessment.