Eyesight numbers · −4.50 explained
Is −4.50 eyesight bad?
−4.50 on the glasses paperwork means the bare eye focuses sharply out to about 22 cm (8.7 inches), closer than comfortable reading, and softens beyond that. That is the moderate band (−3.25 to −6.00): the sharp zone ends inside arm's reach, so lenses are part of getting dressed.
Your glasses number
−4.50diopters
Sharp out to 22 cm bare-eyed. On a wall chart that lands around past the bottom row of a standard chart approximate. With the glasses on, vision at this number is typically a full 20/20.
−4.50 eye prescription, how bad is that?
On the usual scale it is moderate. That is the moderate band (−3.25 to −6.00): the sharp zone ends inside arm's reach, so lenses are part of getting dressed. The number says how far you see without lenses, nothing about how healthy the eye is: a −4.50 eye with the glasses on typically reads a full 20/20 line, and every quarter step either way moves the bare-eye horizon a little.
Where does the blur start at −4.50?
Bare-eyed at −4.50, everything closer than 22 cm is sharp edge to edge. Right at 22 cm the edges start to soften, and past it detail fades rather than disappearing. That horizon is nearer than a phone held normally (30 cm), so nothing on the everyday list is sharp without lenses.
The arithmetic is one line: 100 divided by the number gives the sharp distance in centimeters. 100 ÷ 4.50 = 22.2 cm. Every quarter step on the paperwork moves that horizon, which is why the pages either side of this one read differently.
What glasses number for a computer screen at −4.50?
A lens that focuses exactly at a 60 cm screen would be about −2.75 (the full number less 1.67). The EndMyopia starting point for a close-up pair is −3.25, the full number less 1.25, which leaves the screen just inside the sharp range with a little blur at the far edge.
Try another glasses number
−4.50
- Sharp out to
- 22 cm
- 8.7 in, closer than comfortable reading
- Chart line, bare-eyed
- past the bottom row of a standard chart
- past the bottom row of a standard chart, approximate
The numbers either side
What to do with your number
The full method is a structured 90-day program — proper lenses, measured progress, the things only experience can tune.
EndMyopia members work on lowering their glasses numbers step by step. The whole thing — your numbers explained, lens recommendations, daily habits, weekly check-ins — lives inside BackTo20/20. Full Program $1,788 $149/mo × 12 · lifetime access · money-back guarantee.
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Or keep exploring with the free Eyeball Analyzer (20 minutes, your numbers, what they mean).
Limitations & disclaimer
EndMyopia treats myopia as a refractive state, not a medical condition. This is a free educational tool — not medical advice, diagnosis, or a substitute for a licensed optometrist. Measurements depend on camera quality and how carefully you mark the card edges; expect ±5–10 % on laptops, ±10–15 % on phones. For lens orders, eye health concerns, or any task requiring full 20/20 vision, see a licensed professional.
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