Vision and prescriptions
Visual acuity converter
What does my 20/__ vision mean, and how does it convert to other scales?
Vision and prescriptions
Convert vision scores and understand glasses and contact lens numbers.
Vision and prescriptions
Glasses prescription reader
What do the numbers on my glasses prescription mean?
Vision and prescriptions
Glasses to contact lens converter
What contact lens power matches my glasses prescription?
Vision and prescriptions
Reading glasses strength estimator
Which reading glasses strength should I try first?
Vision and prescriptions
Legal blindness and vision impairment
Does my vision meet the definition of legal blindness?
Vision and prescriptions
Reading print enlargement
How much should I enlarge print so I can read it comfortably?
Vision and prescriptions
Astigmatism vector change
How has my astigmatism changed between two prescriptions?
Glaucoma and optic nerve
Pressure, perfusion and trend tools for glaucoma reports.
Glaucoma and optic nerve
Eye pressure reduction
How much has my eye pressure come down, and how close is it to my target?
Glaucoma and optic nerve
Ocular perfusion pressure
What is my estimated eye perfusion pressure from blood pressure and eye pressure?
Glaucoma and optic nerve
Eye pressure fluctuation
How much do my eye pressure readings vary?
Glaucoma and optic nerve
Nerve fiber layer trend
How fast is my RNFL or GCIPL thickness changing?
Glaucoma and optic nerve
Visual field trend
How is my visual field MD or VFI changing over time?
Glaucoma and optic nerve
Ocular hypertension risk (OHTS)
Where can I estimate my five-year glaucoma risk with ocular hypertension?
Retina and macula
Scan comparisons and self-checks for macular conditions.
Retina and macula
OCT macular thickness change
How much has my central macular thickness changed between scans?
Retina and macula
Amsler grid self-check
Do straight lines look wavy, blurry or missing in one eye?
Retina and macula
Geographic atrophy growth
How fast is my geographic atrophy area growing?
Retina and macula
Ellipsoid zone width change
How has my ellipsoid zone width changed between scans?
Cornea and ocular surface
Cornea measurements and symptom tracking.
Cornea and ocular surface
Endothelial cell change
How much has my corneal endothelial cell count changed?
Cornea and ocular surface
Keratoconus scan comparison
How have my Kmax and corneal thickness changed between scans?
Cornea and ocular surface
Corneal pain and light sensitivity diary
How have my eye pain and light sensitivity varied day to day?
Myopia and children
Track prescription and eye growth over time.
Myopia and children
Myopia and eye growth change
How much has my child's prescription and eye length changed?
Daily care
Plan eye drops and refills.
Daily care
Eye drop schedule planner
How do I fit several prescribed drops into my day?
Daily care
Eye drop refill planner
When will my eye drop bottle run out, and when should I reorder?
Blood pressure and diabetes
Numbers from the rest of the body that matter for the eyes.
Blood pressure and diabetes
Blood pressure category
What does my blood pressure reading mean?
Blood pressure and diabetes
Nighttime blood pressure dip
How much does my blood pressure fall at night on my 24-hour report?
Blood pressure and diabetes
A1c and average glucose
What does my A1c mean in everyday blood sugar numbers?
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About these tools. They explain numbers; they do not diagnose any condition or replace your eye doctor's assessment. Calculations run in your browser, and the values you enter are not sent to us or stored. Medication, surgery and blood pressure decisions remain with your treating clinicians.