Knowing how to read your eyeglass prescription is a must! You might already know if you're nearsighted, farsighted, or dealing with astigmatism, but deciphering it from that prescription slip can be a whole different ballgame. So, we've put together a quick guide to help you figure out how to read your glasses prescription and get those snazzy new eyeglasses ordered ASAP!
If you've had an eye exam and your vision needs have changed, it's crucial to get a new prescription right away. Your optometrist or ophthalmologist will provide you with the updated prescription.
Now, when you want to order glasses from online retailers, they usually ask you to input your prescription on their order form. But if you're not sure how to read your prescription, that whole process can be pretty confusing.
What do all these letters and numbers mean?
Your eyeglass prescription contains essential details for cutting your lenses just right to meet your vision needs. Make sure to keep it updated so that the numbers accurately reflect your eyesight. Your prescription will have various abbreviations and terms, like SPH, CYL, Axis, Prism, PD, and others, each representing important information about your glasses. Stay on top of it to ensure you get the best eyewear for clear vision!
OD vs. OS Eye
OD is short for the Latin term oculus dexter which means right eye.
OS is an abbreviation of the Latin oculus sinister which means left eye. You’ll often see this terms on eyeglass prescriptions.
Sphere, Cylinder, and Axis on Eye Prescriptions
Sphere: The sphere (SPH) on your prescription indicates the lens power you need to see clearly. A minus (-) symbol next to this number means you’re nearsighted, and a plus (+) symbol means the prescription is meant to correct farsightedness.
Cylinder: The cylinder (CYL) number indicates the lens power needed to correct astigmatism. If this column is blank, it means you don’t have an astigmatism.
Axis: An axis number will also be included if you have an astigmatism. This number shows the angle of the lens that shouldn’t feature a cylinder power to correct your astigmatism.
Nearsighted prescriptions
A nearsighted prescription will feature a number with a minus (-) symbol in the ‘sphere’ box. This means your lenses will be shaped to improve your distance vision.
| Sphere | Cylinder | Axis | Prism | Base | ADD | |||
| Distance | OD | -4.00 | ||||||
| Distance | OS | -5.00 | -0.50 | 180 | ||||
Hover on the prescription form to find out what all those number and abbreviations mean
Farsighted prescriptions
A prescription for someone who is farsighted will feature a number with a plus (+) symbol in the ‘sphere’ box. This indicates that your lens should be shaped to correct near vision.
| Sphere | Cylinder | Axis | Prism | Base | ADD | |||
| Distance | OD | +2.00 | ||||||
| Distance | OS | +2.00 | -0.50 | 180 | ||||
Hover on the prescription form to find out what all those number and abbreviations mean
Astigmatism prescriptions
If you have an astigmatism, you will have a number in the ‘cylinder’ column of your prescription that indicates the lens power needed to correct the astigmatism. There will also be a number in the ‘axis’ column that’s needed for astigmatism correction.
| Sphere | Cylinder | Axis | Prism | Base | ADD | |||
| Distance | OD | -4.00 | ||||||
| Distance | OS | -5.00 | -0.50 | 180 | ||||
Hover on the prescription form to find out what all those number and abbreviations mean
Bifocal & progressive prescriptions (multifocal)
A multifocal prescription will include an ADD value, sometimes marked as NV. This indicates the required strength for the near prescription in your lens.
| Sphere | Cylinder | Axis | ADD | |||
| Distance | OD | -4.00 | +2.00 | |||
| Distance | OS | -5.00 | -0.50 | 180 | +2.00 | |
Hover on the prescription form to find out what all those number and abbreviations mean
Prescriptions with prism correction
A prescription for correcting eye alignment issues will include a PRISM and BASE value. These are needed to tell us how to shape the lens so that it can accurately align the wearer’s eyesight. The base value will show either “in” or “out”, or “up” and “down”, indicating the direction the prism should be angled.
| Sphere | Cylinder | Axis | Prism | Base | ADD | |||
| Distance | OD | -4.00 | down | +2.00 | ||||
| Distance | OS | -5.00 | -0.50 | 180 | up | +2.00 | ||
Hover on the prescription form to find out what all those number and abbreviations mean