Understanding Your Eyeglass Prescription: A Simple Guide

Your eyeglass prescription is a short list of numbers that tells a lab how to build lenses for your eyes. Once you can read it, you can pick lenses with a lot more confidence.

What Is an Eyeglass Prescription?

You get an eyeglass prescription after a complete eye exam. It records what your eyes need, and the lab uses those measurements to make your lenses.

The letters look like code at first. SPH, CYL and ADD each describe one fix your eyes need, and the next section takes them one at a time.

Key Terms on Your Eyeglass Prescription

SPH (sphere) tells you if you are nearsighted or farsighted.

• A minus sign (-) means you are nearsighted. You have trouble seeing far away.

• A plus sign (+) means you are farsighted. You struggle to see up close.

CYL (cylinder) measures astigmatism. With astigmatism, the cornea has an uneven shape, so things look blurred or bent. A CYL number on your form means your lenses will correct that uneven curve.

You may also see an “axis” number next to it. The axis gives the direction of that fix, in degrees.

ADD (addition) is extra power for close-up vision. You will see it if you need bifocals or progressive lenses, which is common after age 40. An ADD of +1.75, for example, adds that much strength for close work and eases strain when you read.

Other values may appear too:

• PD (pupillary distance): The distance between the centers of your pupils. It keeps your lenses lined up with your eyes.

• Lens type notes: Your prescription may suggest single-vision, progressive, or bifocal lenses.

How Your Eyeglass Prescription Shapes Your Lens Choices

Your numbers steer the kind of lens you end up with.

SPH affects thickness. A stronger prescription can mean thicker lenses, and high-index lenses keep them thinner and lighter.

CYL and axis keep images sharp. With the right values, the lens matches the shape of your eye and cuts distortion.

ADD puts near-vision help into a progressive or bifocal design. You stop swapping between reading glasses and distance glasses.

See progressive lenses and bifocals and our eyeglass lens options. If you wear contacts, see our contact lenses page.

Screens, Nutrition, and Eye Health

If you spend hours on screens, blue light filtering lenses may help with glare and tired eyes. All About Vision has a guide on whether blue light glasses work.

Food and habits count too. Lutein, zeaxanthin, vitamins C and E, and omega-3s support eye health, as the American Academy of Ophthalmology explains in its diet and nutrition guide.

Bring Your Eyeglass Prescription to Us

Bring your prescription in and our opticians will turn it into glasses. We can walk you through options such as:

• Polarized lenses for outdoor clarity and UV protection

• Progressive lenses for near-to-distance vision in one pair

• Lightweight, durable materials for all-day comfort

We match the choices to your style, your days and your budget. Visit our home page or stop by in person.

Common Questions

Can my prescription change over time? Yes.

It can change as your eyes age or if you develop new conditions. Regular checkups keep your lenses up to date.

How often should I update my glasses? An eye exam every 1 to 2 years is generally recommended, especially for adults 55 and older.

Can I use my eyeglass prescription for contact lenses? No. Contact lens prescriptions include details that eyeglass prescriptions do not, such as lens material and fit. See contact lenses.

What if I lose my prescription? We can help. Our team keeps your records so you can get them when you need them.

Take the Next Step

Golf, books and the Florida sun all ask different things of your lenses, and we can match the lenses to the way you spend your day. Book your eye exam or visit Hindsight Eye Care to get started.