What is Normal Eye Pressure?

October 18, 2019

Measuring eye pressure is an important component of a comprehensive eye exam. What is eye pressure and how is it measured? Keep reading to learn more!


What is normal eye pressure?

Normal eye pressure is between 10 to 21 mmHg (millimeters of mercury – unit of measurement). Although this is the normal range, it is very possible for an individual to have an eye pressure of 9 mmHg or 22 mmHg and still be “normal”. There are several other factors that are considered when determining if a person’s eye pressure is at a safe value, the most important being optic nerve appearance. Contrary to popular belief, blood pressure is not directly correlated to eye pressure. Having high blood pressure may increase the risk of high eye pressure; However, having high blood pressure does not mean that the eye pressure is also elevated and vice versa.


How is eye pressure checked?

There are three common methods of measuring eye pressure: NCT (“air puff” tonometer), Goldmann tonometry, and iCare® (handheld device). All three methods have their pros and cons, but your doctor will determine which test is the best for you given all of the other exam findings. Sometimes it is even necessary to check the pressure using a combination of two methods. It is a recordable value that can be compared from one visit to the next. Therefore, it is measured at every routine exam to determine if there is an increased risk for glaucoma or ocular hypertension.


What’s the big deal with high eye pressure?

If the eye pressure is elevated, it can be a sign of glaucoma or ocular hypertension. Glaucoma is a chronic, progressive condition that causes damage to the optic nerve. The damage is typically related to increased eye pressure. On the other hand, it is possible to have high eye pressures without glaucomatous damage. This is called ocular hypertension, which literally just means high eye pressure. Ocular hypertension is monitored closely to ensure the optic nerves stay healthy versus developing glaucoma.


Are there ways to maintain normal eye pressure?

When the eye pressure becomes too high or glaucoma-related damage is occurring to the optic nerves, the initial treatment for lowering eye pressure is a prescription eye drop, typically at bedtime. There is no cure for glaucoma, so the only way to minimize the risk of vision loss is by decreasing the eye pressure. Living a healthy lifestyle with normal blood pressure, regular exercise, and a healthy diet can also help maintain normal eye pressure.



There are no symptoms associated with mildly elevated eye pressure, which can lead to vision loss and optic nerve damage over time. Therefore, early detection of glaucoma is important for initiating treatment as soon as possible. Schedule your annual eye examination to ensure you are maintaining proper eye health and normal eye pressure.