Is -1.50 Myopia Bad?
Short answer: −1.50D is mild myopia. Your distance vision is meaningfully blurred without correction, but at this prescription, the structural risk to your eyes is still low. Progression rate matters more than the current number.
Where -1.50 sits in the risk spectrum
Myopia severity is better understood through axial length (the physical length of the eye in millimetres) than through the diopter number alone. Two people can have the same prescription from different amounts of axial elongation — and axial length is what determines long-term structural risk, not the diopter number itself.
| Prescription | Approx. axial length | Structural risk category |
|---|---|---|
| -1.00D | ~24.2mm | Low |
| -2.00D | ~24.7mm | Low–Moderate |
| -3.00D | ~25.2mm | Moderate |
| -4.00D | ~25.8mm | Moderate–High |
| -5.00D | ~26.1mm | High |
| -6.00D | ~26.6mm | High (IMI threshold) |
| -8.00D | ~27.5mm | Very High |
| -10.00D | ~29.0mm | Extreme |
AL–refraction mapping is approximate (±2–3D individual variation). Based on Flitcroft 2012; Tideman et al. 2016. Your row is highlighted.
Clinical perspective
−1.50D corresponds to an axial length of approximately 24.2–24.7mm — low-risk territory. Retinal detachment and maculopathy risks are not significantly elevated until axial length approaches 26mm (approximately −6.00D). Annual monitoring with refraction is standard.
For parents: what this means for a child at -1.50
−1.50D in a child is not alarming on its own — the concern is how fast it is changing. If your child went from −0.75D to −1.50D in one year, that's 0.75D of change in 12 months, which exceeds the clinical threshold for fast progression. Track the rate, not just the number.
What to do at -1.50
Management is typically considered if the child is young and progressing faster than 0.50D/year. At −1.50D with slow progression, watchful monitoring is appropriate.
Calculate your exact progression rate
Enter age and two axial length measurements. Get progression rate, AL percentile, and projected prescription at age 18 — with and without treatment.
Check progression now →This page is for educational purposes and does not constitute medical advice. Diopter-to-axial-length conversions are approximations (±2–3D individual variation). MyopiaTracker is a decision-support tool — not a diagnostic device. Consult a qualified optometrist or ophthalmologist for personalised advice.