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Ophthalmology & Optometry/measuring vision and converting measurements


How do I convert the findings of a European optometrist of my vision into the standard measurement used in the US?
I was given findings of 1/10  and4/10..  I believe the american system uses the Snellen system, correct?

Hi Paula,
snellen is based on 20 feet so normal is a ratio of 20/20 equals 1.  Europeans use 6 meters, so 6/6 equals normal or the ratio of 1.  any testing can be used, and as long as we are talking about far not near, the ratio is what matters, some countries use only the ratio: so 1/10 would be 20/200 or 6/60 or 0.1.   4/10 would be 20/50 or 6/15 or 0.4.
Hope that helps,
Mitch Axelrod, OD

Ophthalmology & Optometry

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Mitchell Axelrod


I'm happy to answer questions about eye exam findings and procedures, glasses and contact lens types/prescriptions/problems. I can also answer questions about general eye conditions/diseases. I do not answer questions concerning surgical techniques/procedures. Please state your age or within a small range when asking questions, as it is often important.


Optometrist 19 yrs.

Doctor of Optometry, cum laude; Residency in Ocular Disease

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