Understanding your contact lens prescription is essential for ordering the correct lenses. Our comprehensive guide explains every term and measurement you'll see on your prescription.
| SPH | CYL | Axis | BC | DIA | Brand | |
|---|---|---|---|---|---|---|
| OD (Right) | -2.50 | -1.25 | 180 | 8.6 | 14.2 | Acuvue Oasys |
| OS (Left) | -2.25 | -1.00 | 175 | 8.6 | 14.2 | Acuvue Oasys |
Additional Notes:
Right eye. This is the standard abbreviation used by eye care professionals.
Left eye. The Latin term for the left eye.
Both eyes. Used when the prescription is the same for both eyes.
The main lens power needed to correct nearsightedness (-) or farsightedness (+).
The lens power for astigmatism correction. Always has a minus (-) sign.
The orientation of astigmatism correction, measured in degrees (1-180).
The curvature of the lens that matches your eye's shape (typically 8.0-9.0mm).
The width of the lens in millimeters (typically 13.0-15.0mm).
The magnifying power for multifocal lenses, always a plus (+) number.
The specific manufacturer and product line recommended by your eye doctor.
Look for "OD" (right eye) and "OS" (left eye). Some prescriptions may use "OU" if both eyes have the same prescription.
This indicates your main vision correction. Negative numbers (-) correct nearsightedness, positive numbers (+) correct farsightedness.
If you have astigmatism, you'll see CYL and Axis values. CYL is always negative, and Axis ranges from 1-180 degrees.
These measurements ensure proper fit. Your eye doctor determines these based on your eye measurements.
Your doctor will specify which brand and product line is best for your eyes and lifestyle.
SPH: Negative numbers (e.g., -2.50)
Symptoms: Difficulty seeing distant objects clearly
Common Lenses: Daily disposables, monthly lenses, toric for astigmatism
SPH: Positive numbers (e.g., +2.50)
Symptoms: Difficulty seeing close objects clearly
Common Lenses: Daily disposables, monthly lenses, multifocal options
CYL: Always negative (e.g., -1.25)
Axis: 1-180 degrees (e.g., 180°)
Symptoms: Blurred or distorted vision at all distances
Common Lenses: Toric lenses specifically designed for astigmatism
ADD: Positive numbers (e.g., +2.00)
Symptoms: Difficulty focusing on close objects after age 40
Common Lenses: Multifocal or bifocal contact lenses
Contact your eye doctor or check your last prescription card.
Upload a photo of your prescription for verification.
Find an eye doctor near you for a new prescription.