Is -1.00 Myopia Bad?
Short answer: No — −1.00D is mild myopia. You'll need glasses or contacts for distance vision, but structural risk to your eyes at this prescription is minimal. The real question is whether it's still progressing.
Where -1.00 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
At −1.00D, axial length is typically 24.0–24.4mm — well within the low-risk zone. The IMI defines myopia as ≤−0.50D; −1.00D falls in the low-severity band. Annual monitoring is appropriate but intervention is usually not indicated unless progression is fast (>0.50D/year).
For parents: what this means for a child at -1.00
If your child's prescription is −1.00D, the priority is tracking the progression rate — not the current number. A child who reaches −1.00D at age 7 and is progressing 0.75D/year needs attention. A child at −1.00D at age 14 who is stable does not.
What to do at -1.00
Treatment is typically not indicated at −1.00D unless the patient is young (under 10) and progressing rapidly. Monitoring every 6–12 months is the standard approach.
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.