Pupillary Distance (PD) is the measurement between the centers of your pupils, typically in millimeters. It ensures that your lenses are aligned correctly with your eyes—a crucial detail for clear, comfortable vision.
PD can be a single value (binocular PD) or two separate values for each eye (monocular PD).
PD may vary for different prescriptions, such as distance and reading glasses. For instance, a distance PD might be 59 mm, while a reading PD could be 56 mm, reflecting the different focal points required for far and near vision.
Additionally, for progressive lenses, use your distance PD unless otherwise specified.
Some common symptoms of incorrect PD alignment include eye strain, headaches, dizziness, and a feeling of visual discomfort.
An incorrect PD can cause your lenses to misalign with your pupils, leading to visual discomfort such as eye strain, headaches, dizziness, blurriness, or a "crossed-eye" sensation.
👁️ How to Get Your PD:
Check your prescription: Your eye doctor may have already included your PD from your last exam. Professional measurement is the most reliable method.
Use our PD measuring tool: If you don’t have it, no problem! During checkout, you’ll find an easy-to-use PD tool on the prescription entry page. It only takes a minute and gives accurate results using your device’s camera. However, app-based tools can be less reliable due to lighting and camera angles.
You can also measure your PD at home:
Stand about 8 inches from a mirror.
Hold a ruler against your brow.
Close your right eye and align the 0 mm mark with the center of your left pupil.
Close your left eye and open your right eye. Read the millimeter mark aligned with the center of your right pupil.
Typical PD ranges: Adults ~54–74 mm, children ~43–58 mm.
Repeat for accuracy.
💡 A correct PD helps make sure your lenses perform exactly as they should—especially for higher prescriptions.
If your prescription lists separate monocular PDs (e.g., 30 mm for the right eye and 31 mm for the left eye), enter these values individually for greater accuracy. If your PD includes a decimal (e.g., 62.5 mm), round to the nearest whole number if the system doesn't support decimals; a 0.5 mm difference is typically within acceptable tolerance.
Differences of up to 4 mm are generally acceptable and should not affect vision. However, larger differences, such as 5 mm or more, may result in discomfort and require attention. Additionally, some frames may not support certain PD ranges. If you encounter an error, contact support or choose a different frame.