Understanding your eyeglass prescription can be confusing, especially when it includes terms like ADD. This value plays a key role in supporting near vision and reading, particularly for those experiencing presbyopia. Knowing what ADD means and how it affects your lenses helps you choose eyewear that offers the right balance of clarity and comfort.
The term ADD stands for "Addition" and refers to the additional magnifying power required to correct near vision, typically due to presbyopia—a condition that affects the ability to focus on close objects as people age.
This value is added to the distance prescription to create the near-vision correction. For example, if your distance prescription is +1.00 diopter and your ADD is +2.00 diopters, your near-vision power becomes +3.00 diopters.
Around age 40, the eye’s natural lens loses flexibility, reducing the ability to focus on close objects—a condition known as presbyopia. Symptoms often include difficulty reading, eye strain, and discomfort during prolonged screen use.
The ADD value provides the additional magnification needed for near vision while keeping distance vision clear. It allows multifocal lenses to support both reading and distance viewing—eliminating the need to switch between multiple pairs of glasses..
The ADD value usually appears as ADD or NV (Near Vision) on your prescription, listed alongside SPH, CYL, and AXIS. It’s typically a positive number, sometimes different for each eye, indicating how much extra magnification is required for close-up clarity.
During an eye exam, your optometrist measures this through a refraction test, checking how your eyes focus at different distances. You may be asked to read symbols on a near chart until the clearest focus is achieved. The correct ADD value ensures your lenses deliver smooth, comfortable vision for reading, computer work, and other close tasks.
An ADD value is typically prescribed for people who struggle to focus on close objects due to presbyopia, a natural part of aging that usually begins around age 40. It’s also helpful for individuals who already wear glasses for nearsightedness, farsightedness, or astigmatism and now need extra support for reading or computer work.
In these cases, the ADD value complements the distance prescription, creating a single pair of lenses that restores clear vision at all ranges. Whether you spend long hours on digital screens or frequently switch between near and far tasks, lenses with the right ADD value can provide comfort, convenience, and sharper focus.
The ADD value is essential in several types of eyeglasses to choose:
Understanding the ADD value to ensure clear focus and visual comfort across all distances. Discover Eydology’s collection of multifocal and reading lenses designed to match your prescription and lifestyle needs. A choice you'll never regret
