Free Tool
Axial Length Percentile Projector
One measurement is enough to start. See exactly which percentile lane your child's eyes are on, where that lane lands at age 18 — axial length and estimated refraction — and how urgent the situation is.
Interactive
Where does your child's lane end at 18?
One measurement per eye is enough to start. Enter your child's age and the latest axial length for each eye (from any biometry report — plus the measured refraction, if the report has it), pick the reference population that matches your child — the CREAM consortium's European/Australian database (sex-specific curves, ages 6–18) or the Chinese reference (sex-combined, ages 3–18) — and we pinpoint each eye's exact percentile lane, project it to age 18 (axial length and estimated refraction), and grade the risk. Same report format as the 6S tracker: this page does the first-measurement estimate; the tracker does the long-term management.
CREAM curves are sex-specific.
Axial length — percentile lanes and projection to 18
Refraction projection to 18 — starts from your measured value if entered, else the axial-length rule of thumb
Reference data, two options: (1) sex-specific axial-length percentiles for European/Australian children aged 6–21, from the CREAM (Consortium for Refractive Error and Myopia) population database; (2) sex-combined percentile curves for Chinese children aged 3–18. Chinese eyes run longer on average — pick the population your child belongs to for the most meaningful lane. Method note: the projection assumes the eye holds its current percentile lane to age 18 — a simplification used for orientation, not a clinical prediction. The refraction estimate applies the rule of thumb of −2.5 to −3.0 D per mm beyond a 24 mm emmetropic baseline; actual refraction depends on corneal and lens power, which axial length alone cannot see; growth spurts and interventions also move the outcome. If you also enter the measured refraction from the same visit, the refraction projection starts from that number instead of the axial-length-only estimate. Axial length around 26 mm and beyond is the range where high-myopia complications climb steeply. Educational tool, not medical advice.
How it works
Enter the measurement
Age plus the latest axial length from any biometry report — enter each eye you have (left required, right optional), plus the measured refraction if the report has it. Pick the reference population that matches your child: CREAM European/Australian curves (sex-specific, ages 6–18) or the Chinese reference (ages 3–18).
Find the lane
The tool anchors the eye on the P5–P95 percentile curves. The lane matters more than the number: a child at a "normal" value who is climbing lanes is still accelerating toward myopia — and that climb is visible years before blur.
Project, grade, share
The lane extends to age 18, with an estimated refraction and a four-level risk grade (Low / Moderate / Elevated / High). Download the chart as a PNG or copy the share text — bring it to your next appointment, or post it to compare notes with other parents.
What the lanes tell you
Children's eyes grow along percentile lanes. P50 is the median child; lanes above P75 at a young age mean the eye is longer than three-quarters of peers — and length is the thing that drives myopia. The earlier you know the lane, the cheaper the intervention: light, outdoor time, optical defocus and disciplined tracking beat late, aggressive corrections every time. For the growth-rate numbers behind this tool, see average axial growth rate by age; for what counts as normal at the most-asked age, normal axial length at age 7.
Don't project once. Track every 3 months.
The free 6S tracker anchors every measurement to the percentile curves and flags lane-climbing automatically.