What Does SPH, CYL and AXIS Mean on My Glasses Prescription?

What Does SPH, CYL and AXIS Mean on My Glasses Prescription?

If you've ever looked at your glasses prescription and wondered what all the abbreviations mean, you're not alone.

Terms like SPH, CYL and AXIS can seem confusing at first, but they simply describe how your lenses should be made to give you clear vision.

Here's what each part of your prescription means.

What Does SPH Mean?

SPH stands for Sphere.

This number tells you how much lens power is needed to correct short-sightedness (myopia) or long-sightedness (hyperopia).

A minus (-) number means you're short-sighted, making distant objects appear blurry.

A plus (+) number means you're long-sighted, making close-up tasks more difficult.

The larger the number, the stronger the prescription.

What Does CYL Mean?

CYL stands for Cylinder.

This value measures the amount of astigmatism you have.

Astigmatism occurs when the front of the eye isn't perfectly round, causing light to focus unevenly and making vision appear blurred or distorted.

If your CYL box is blank or shows zero, you don't have a measurable amount of astigmatism requiring correction.

What Does AXIS Mean?

AXIS works alongside the CYL value.

It's measured between 1 and 180 degrees and tells the laboratory exactly where the astigmatism correction should be positioned within the lens.

AXIS doesn't indicate how strong your prescription is. It simply describes the direction of the correction.

What Does ADD Mean?

Some prescriptions also include an ADD value.

This is an additional reading prescription used in bifocal or varifocal lenses.

If you only wear single-vision glasses, your prescription may not include an ADD value.

What About Prism?

Some prescriptions contain Prism measurements.

These are used to help correct eye alignment problems and are only included when needed.

Not everyone will have Prism on their prescription.

Why Are There Separate Values for Each Eye?

Your right and left eye often require different corrections.

That's perfectly normal.

Each eye is measured individually to provide the clearest possible vision.

Can I Order Glasses Online Using My Prescription?

Yes.

As long as you have a current prescription and know your Pupillary Distance (PD), you can usually order single-vision glasses online.

The important thing is to enter every value exactly as it appears on your prescription.

Even a small typing error can affect your vision.

Common Mistakes to Avoid

When entering your prescription online, double-check that you:

• Keep the plus (+) or minus (-) sign.

• Enter the right eye and left eye correctly.

• Don't confuse CYL with AXIS.

• Use your current prescription.

• Enter your PD accurately.

Taking an extra minute to check your prescription before placing an order can help avoid unnecessary delays or remakes.

Understanding Your Prescription

Your glasses prescription may look complicated, but each value has a simple purpose.

Together, they allow your lenses to be manufactured specifically for your eyes, helping you enjoy clear, comfortable vision every day.

If you're ever unsure about any part of your prescription, it's always worth asking before placing an order rather than guessing.