How to read eye exam results

How to read eye exam results

Eye exam results may seem challenging to understand due to industry terms used by opticians like Prism, Axis, Cyl, and Sph, along with their respective measurements. However, these results represent the accurate lens correction necessary to improve your vision. Your optician uses these digits to determine your lens’s shape, angle and cut.

In the UK, eye test results use a standard format that includes several unique measurements for each eye. Continue reading to learn how to read eye exam results.

How to read eye exam results

During eye tests, opticians precisely note various key values for every eye. Here is an explanation of what those results mean:


The Sph or sphere value is the strength or power of your lens. Many people who wear glasses probably know this as their lens power number, which could either be minus or plus. People with a plus lens number like +2.75 are long-sighted, so things up close often seem more blurred. In contrast, a minus sphere number, such as -2.75, indicates short-sightedness, where you find it challenging to focus or see distant objects.

Cyl and Axis

The Cyl or cylinder value refers to the condition of astigmatism, and it examines your eyeball’s curvature and any deviations. To correct this issue, opticians recommend a Cyl value opposite and equal to your eye’s astigmatism. Hence, the Cyl value represents those precise modifications that will improve your vision.

Cyl and Axis measurements work simultaneously and complement each other. The axis measurement, anywhere from 1 to 180 degrees, describes the best place to set up the astigmatism corrections on the lens.

Base and prism

If a person’s eye muscles are not working together properly, opticians can use the base and prism values to rectify them. Base refers to the direction, whether in, out, up or down, while the prism is a value that moves up in increments of 0.5.

My vision has changed: Do I need another eye exam?

It is common for eyeglass prescriptions to change with time. In such cases, it is helpful to book a comprehensive eye test to help modify the power of your eyeglasses. This change is typically age-dependent, where short-sightedness is common in childhood, whereas presbyopia affects people at around 45 years.

When to get an eye test Cardigan based

If you are experiencing vision difficulties, you should book an eye test Cardigan based promptly. That way, you can get a diagnosis on time and get the necessary treatment that will allow you to live your life to the fullest.

However, if you do not have an underlying vision condition, it is best to schedule an eye exam with an optician at least every year. Kids should get an eye exam at six years before they begin school to ensure their vision works correctly since poor vision may affect learning. Do you have any vision problems and wish to learn how to read eye exam results? Book your appointment now at Pritchard Cowburn Opticians or get in touch today to get your comprehensive eye exam. We offer a wide range of eye tests, including NHS eye tests and enhanced Visiplan eye examinations.