Is -6.00 Myopia Bad?

Short answer: Yes — −6.00D meets the clinical definition of high myopia. This is not a cosmetic difference from −3.00D; it carries meaningfully elevated lifetime risk of retinal detachment, myopic maculopathy, and glaucoma. The good news: with proper monitoring and care, most people with −6.00D maintain good vision throughout their lives.

High (clinical threshold) myopia · Approx. axial length: ~26.2–27.0mm

Where -6.00 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.

PrescriptionApprox. axial lengthStructural risk category
-1.00D~24.2mmLow
-2.00D~24.7mmLow–Moderate
-3.00D~25.2mmModerate
-4.00D~25.8mmModerate–High
-5.00D~26.1mmHigh
-6.00D~26.6mmHigh (IMI threshold)
-8.00D~27.5mmVery High
-10.00D~29.0mmExtreme

AL–refraction mapping is approximate (±2–3D individual variation). Based on Flitcroft 2012; Tideman et al. 2016. Your row is highlighted.

Clinical perspective

−6.00D (or axial length ≥26mm) is the IMI's threshold for high myopia. Tideman et al. 2016 demonstrated approximately 5× higher retinal detachment risk at 26mm vs 24mm. Myopic maculopathy affects an estimated 40% of high myopes by their 60s in some East Asian cohorts. Bi-annual dilated ophthalmoscopy and optical coherence tomography of the macula become standard components of care.

For parents: what this means for a child at -6.00

A child reaching −6.00D during childhood is in a high-risk category for lifetime visual impairment. If they're not yet 18 and are still progressing, aggressive myopia management — including combination therapy — is warranted immediately.

The number that matters most is not the prescription — it's the rate of change. A child going from -6.00 to -6.75D in one year is progressing faster than a child going from -5.50D to -6.00 over two years. Enter two measurements in MyopiaTracker to calculate the actual progression rate.

What to do at -6.00

Adults with stable −6.00D: dilated eye exam every 6–12 months minimum; immediate referral for any new floaters, flashing lights, or visual field changes (retinal detachment warning signs). Children still progressing: combination therapy and ophthalmology co-management.

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 →
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Sources: Tideman JWL et al. JAMA Ophthalmol. 2016;134(12):1355–1363 (axial length risk) · Flitcroft DI. Prog Retin Eye Res. 2012;31(6):622–660 (AL–refraction modelling) · IMI 2025 Digest · Holden BA et al. Ophthalmology. 2016 (global prevalence)

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.