How to Read a Contact Lens Prescription (2024)

Table of Contents:

• Contact Prescription Abbreviations and Terms
• How to Read a Toric Contact Lens Prescription for Astigmatism
• How to Read a Multifocal Contact Lens Prescription for Presbyopia
• What Does a Contact Lens Prescription Look Like?
• How to Read a Contact Lens Prescription on the Box
• Different Lens Types
• FAQ

Understanding your contact lens prescription can be confusing at first, but you’re not alone. The numbers and abbreviations may seem overwhelming, but deciphering them is simpler than you might think. Knowing what each term means is essential not only for ordering the correct lenses but also for maintaining your eye health. In this guide, we’ll walk you through everything you need to know, from key abbreviations to special terms for conditions like astigmatism and presbyopia, helping you make sense of it all.

Your contact lens prescription likely appears as a grid or table with various numbers and abbreviations. Understanding these terms is essential for ordering the correct lenses:

OD: OD (Oculus Dexter) refers to your right eye

OS: OS (Oculus Sinister) refers to your left eye.

OU: (Oculus Uterque) Sometimes you might also see this and it is shorthand which refers to both eyes i.e. the powers are the same for both eyes.

Brand: This specifies the brand of contact lenses prescribed by your optometrist. Each brand has unique features and measurements, so you must order the exact brand listed on your prescription. Switching brands or trying new lenses requires speaking with your eye doctor and is important to mention when meeting for your eye checkups. Popular brands include , CooperVision’s Biofinity, and Alcon’s Air Optix.

BC (Base Curve): This number, measured in millimeters, represents the curvature of the contact lens. It should align with the curvature of your eye, typically ranging between 8.0 and 9.0. For example, you might see BC 8.4 or BC 8.6. If you switch lenses the Base Curve may change while your powers remain the same. Many brands have only one Base Curve however an important note: Some contact lens brands come in multiple Base Curves so pay close attention to the numbers on your box or prescription when ordering.

DIA (Diameter): The diameter of the lens, also measured in millimeters, usually ranges between 14.0 and 14.5. This ensures the lens fits comfortably over your cornea.

PWR/SPH (Power/Sphere): This indicates the strength of your prescription in diopters. Negative numbers (e.g., -2.00) correct nearsightedness, while positive numbers (e.g., +2.00) correct farsightedness. Pay close attention when ordering your lenses to select the correct Minus (-) or Plus (+).

Expiration Date: Most contact lens prescriptions expire in 1 to 2 years, depending on state regulations. This date ensures your prescription is current and your eye health is regularly monitored.

How to Read a Contact Lens Prescription for Astigmatism

If you have astigmatism in one or both eyes, your prescription will include additional terms:

CYL (Cylinder): This measures the lens’s cylindrical shape needed to correct astigmatism, expressed in diopters and can be positive or negative.

AXIS: This indicates the orientation of the astigmatism in degrees, ranging from 0 to 180. For contact lens prescriptions the Axis will ONLY come in options of 10s. For example 10, 20, 30, 40, etc… through 180.

How to Read a Multifocal Contact Lens Prescription for Presbyopia

For presbyopia, you’ll see these additional terms:

ADD (Addition): This indicates additional magnification for near vision, either as a number in diopters or as a level (low, medium, high).

D/N (Dominant/Nondominant): Some multifocal lenses use this to differentiate correction for distance (dominant eye) and near vision (nondominant eye).

Your contact lens prescription will contain the terms and numbers mentioned above, tailored to your specific vision needs. Here are some examples:

A Spherical Contact Lens Prescription for Nearsightedness Example:

A Toric Contact Lens Prescription for Astigmatism Example:

A Multifocal Contact Lens Prescription for Presbyopia Example:

These examples should help you identify and interpret the different elements of your prescription.

How to Read a Contact Lens Prescription on the Box

The details on the contact lens box may differ slightly from your written prescription. Ensure the prescription strength information on the box matches your optometrist’s prescription. Commonly listed terms include:

Power (PWR/SPH): The vision correction strength.

Base Curve (BC): The curvature of the lens.

Diameter (DIA): The size of the lens.

Understanding Different Lens Types

Spherical lenses correct common vision issues like nearsightedness and farsightedness. Toric contact lenses are designed to correct astigmatism with a unique shape that stabilizes the lens. Multifocal contact lenses provide clear vision at various distances, making them ideal for presbyopia. Toric multifocal lenses combine the benefits of toric and multifocal lenses, catering to those with both astigmatism and presbyopia. For more detailed information on each type, read our Guide to Three Main Types of Contact Lenses here.

FAQ

What does toric mean? Toric lenses are designed to correct astigmatism. They have a unique shape that provides different refractive powers on the vertical and horizontal orientations, allowing for precise vision correction.

How many boxes should you order at a time? The number of boxes you need depends on your wearing schedule. For example, one box of monthly lenses is enough for six months for one eye. To cover both eyes for a year, you would need four boxes. For daily lenses, consider ordering larger quantities to ensure a steady supply.

Can I order contact lenses using my glasses prescription? No, a glasses prescription for contact lenses will NOT work and the contact lenses will not provide the right correction, not fit or stay on your eye, or both. You must be fit and have received a contact lens prescription from an eye care provider.

What if I can’t figure out my prescription? Should I just guess? No, you should never guess your prescription. Contact us with any questions, and if possible, send a picture of your prescription or contact lens boxes. We can help identify the exact lenses prescribed for you.

Now You’re Confidently Navigating Your Lens Prescription

Understanding your contact lens prescription doesn’t have to be overwhelming. By familiarizing yourself with the key terms and abbreviations, you can ensure you’re ordering the correct lenses for optimal comfort and vision. This knowledge not only helps you make informed decisions but also supports your overall eye health. Remember, if you’re ever in doubt which numbers go where, reach out to us anytime for guidance, we’re here to help. Equipped with this information, ordering your contact lenses will be a breeze!

Helpful Links:

• Answers Page
• Insurance Information
• Shop for Contact Lenses

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