Could you add another option to the Development Stage Calculator?

Last updated on May 29, 2026

Question:

Hello,

This is not a question but feedback.

Could you add an option to choose the puberty start time on the Tanner test?

I am 18, almost 19, but my puberty began when I was almost 15, so my real age does not match my physical age. I don’t know how much chronological age impacts test scores, but it would be cool to have that option.

Best.

Answer:

I am glad you asked. I’m willing to consider improvements.

What do you consider to be the start of puberty? For most boys, they consider it to be the first noticeable sign that they are changing, such as when pubic hair starts to show or when they first have an erection. Since the definition varies by person, I instead ask whether the various markers appeared. Thus, indirectly, I am asking if you passed puberty.

While the timing of the various markers varies among individuals, they fall into a rough pattern. For example, when you state that you have hair between your belly button and your groin, that tells me that you are at least in stage 4. Each stage lasts about two years, so that tells me that Stage 2 started about four years ago. Since I also know your age is nearly 19, I can reasonably guess that puberty started for you just before you turned 15.

What I haven’t done is print out the estimated time puberty started for you. I’ll think about adding a question to ask a guy when he thinks puberty started for him. That would give another cross-check on the data.

Question:

Hi, and thanks for the reply.

I consider puberty to start when the testicles begin to grow. I was monitored for delayed puberty by doctors, so I got to know the exact starting time (14y 9mo). The doctor said that it had ”just started”. If it hadn’t, they would have started it medically. I understand that it’s hard or nearly impossible for most boys to know when their balls start growing, so I think that the hair in the groin would be a good sign instead. I got hair there about 7 months after my puberty started.

And yeah, I’m almost done with puberty. 4.7 is my stage. I’m still growing in height. I grew 6 cm at 17-18, and it won’t just stop there. 

If you’d like, I could list all the pubertal changes I have experienced in order. I used to (and still do) keep track of the changes in my body very closely. 

I figure it might help other boys with delayed puberty figure out when they might experience specific changes (beard, voice change, etc.).

Answer:

That would be fine. I’ll try to figure out a way to share it on the site.

Response:

This table is pretty much all I remember. I don’t remember much between 16 and 17, only that my body hair began to thicken and spread, and that my shoulders kept widening noticeably.

Note: I was prescribed HGH (growth hormone) treatment, so my growth may be above average for my skeletal age. However, I am not completely certain whether this is true.

AgeHeight
Skeletal Age
TannerTesticle Volume
Left / Right
Additional Info
14 and 9 months144.1
10.5 yr.
Genital 2 Pubic 22.7 ml / 2.7 mlPuberty started.
15 and 5 months
—————
15 and 7 months—————
15 and 8 months
146.1Genital 2 Pubic 25.7 ml / 5.7 mlHair growth in the groin started.
—————
Started feeling horny
—————
First ejaculation
16 and 1 month—————
16 and 5 months
153.1
12.2 yr.
Genital 3 Pubic 3Armpit hair began to appear
—————
Voice change began
16 and 7 months158.1Gential 3 Pubic 4
17 and 1 month162.1
14.0 yr.
Gential 3 Pubic 4
17 and 8 months166.2Genital 4 Pubic 5Shoulders continue to widen during the next year.
18 and 4 months169.5Genital 5 Pubic 5Dark, thin hair started to grow on the upper lip. Lighter hair started to grow on the cheeks and on the sides of the neck. Chest hair started at this point, too, as well as a happy trail.
18 and 10 months171.4
16.8 yr.
Genital 5 Pubic 515 ml / 24.8 mlHair already started to spread out to thighs. 

I don’t know whether this is helpful, but at least it is something.