Tanner Stage Finder: Identify Puberty Stages I–V
How This Differs From Our Peak Height Velocity Calculator
Our Peak Height Velocity Calculator already uses pubertal signs to estimate where a child is in their growth spurt — approaching it, at it, or past it. This tool has a narrower, different job: it's a straightforward reference lookup that tells you which of the five standard Tanner stages a physical description matches, and what age range that stage is typically seen in. It does not calculate a growth phase, a peak height velocity window, or a predicted adult height — for any of those, the Peak Height Velocity Calculator or the Child Height Prediction Calculator is the right tool.
Think of the two as complementary: this tool answers "which stage is this?", while the Peak Height Velocity Calculator answers "what does that mean for the growth spurt?"
What Are Tanner Stages?
The Tanner staging system, developed by researchers James Tanner and W. A. Marshall from long-term studies of children published in 1969 and 1970, remains the standard clinical framework for describing the sequence of physical puberty.1,2 It breaks puberty into five stages (I through V) for each of three markers: breast development in girls, genital development in boys, and pubic hair growth in both sexes. Stage I represents the prepubertal state, and Stage V represents adult maturity.
Because the tempo of puberty varies widely between individuals, two children of the same age can be at very different Tanner stages, and that's considered entirely normal. The staging system describes sequence and pattern, not a fixed timetable.
Tanner Stages: Full Reference Tables
Breast Development (Girls)
| Stage | Description | Typical Age Range |
|---|---|---|
| I | No glandular breast tissue; prepubertal appearance | < 8 years |
| II | Breast bud forms with a small area of surrounding tissue; areola begins to widen | ~8–13 years |
| III | Breast tissue extends beyond the areola, which continues to widen but stays in the same contour as the breast | ~10–14 years |
| IV | Areola and nipple form a raised, secondary mound above the breast contour | ~11–15 years |
| V | Adult breast size and contour; areola returns to the general breast contour | ~13–18 years |
Genital Development (Boys)
| Stage | Description | Typical Age Range |
|---|---|---|
| I | Testes, scrotum, and penis are childlike in size and proportion | < 9.5 years |
| II | Scrotum and testes enlarge; scrotal skin reddens and changes texture; little penis growth yet | ~9.5–13.5 years |
| III | Penis begins to lengthen; testes and scrotum continue enlarging | ~11–14.5 years |
| IV | Penis increases in width as well as length; testes and scrotum enlarge further; scrotal skin darkens | ~12–15.5 years |
| V | Genitalia reach adult size and shape | ~13–17 years |
Pubic Hair Growth (Both Sexes)
| Stage | Description | Typical Age Range |
|---|---|---|
| I | No pubic hair present | < 9 years |
| II | Sparse, downy hair with slight pigmentation appears at the base of the genitals | ~9–13.5 years |
| III | Hair becomes coarser and more curled, and starts spreading sideways | ~10.5–14.5 years |
| IV | Adult-textured hair covering a smaller area than the eventual adult pattern | ~12–15.5 years |
| V | Adult quantity, texture, and distribution, extending to the inner thighs | ~13–17 years |
Age ranges are approximate, drawn from the original Marshall and Tanner longitudinal studies.1,2 They describe the range seen in healthy children, not a strict pass/fail cutoff.
When Timing Falls Outside the Typical Range
Two clinical thresholds are widely used to flag pubertal timing worth discussing with a pediatrician3:
Neither threshold is a diagnosis on its own — plenty of early or late developers turn out to be entirely healthy variations — but both are reasonable, well-established reasons to bring the timing up at a check-up.
Frequently Asked Questions
Do breast development and pubic hair always match the same stage?
Not necessarily. It's common for one marker to run slightly ahead of or behind the other in the same child, which is why this tool lets you check each marker separately.
Does this tool tell me when the growth spurt will happen?
No. This tool only classifies the current stage. For growth-spurt timing and phase, use our Peak Height Velocity Calculator, which is built specifically for that question.
Who normally assesses Tanner stage?
In a clinical setting, a pediatrician performs this assessment directly. This tool is meant as a plain-language educational reference for parents, not a substitute for a clinical exam.
Is it normal for stages to take a while to progress?
Yes. The original research found the full progression from the first sign of puberty to adult maturity typically takes around 3 years on average, though the pace varies a great deal between individuals.1,2
What should I do if the age doesn't match the typical range?
A single reading outside the typical range isn't an emergency, but it's a reasonable thing to mention at a pediatric visit, particularly if it aligns with the precocious or delayed puberty thresholds above.
