PD Calculator
Measure your pupillary distance at home — needed for accurate prescription lenses.
💡Stand 20 cm (8 in) from a mirror. Place a mm ruler flat across your nose bridge. Close your right eye and align the ruler's 0 mm mark with your left pupil centre. Open your right eye, close your left, and read the mm mark at your right pupil. That number is your binocular PD.
Enter your measurements
mm
— or enter each eye separately (monocular PD) —
mm
mm
Near or distance vision?
Your Pupillary Distance
💳Uses a standard credit card (85.6 mm wide) as a scale reference. Hold it across your nose at eye level, take a photo, then open the photo in an image editor that shows pixel coordinates (Paint on Windows, Preview on Mac) and enter the values below.
How to take the photo
- Hold a credit card horizontally across the bridge of your nose, at eye level.
- Look straight ahead — keep your head level and gaze forward.
- Have a friend take the photo from ~50 cm away. The card must appear horizontal.
- Open the photo and note the pixel x-coordinates of: left card edge, right card edge, left pupil centre, right pupil centre.
px
px
px
px
All x-coordinates measured from the left edge of the image.
Your Pupillary Distance
📷Upload a photo holding a credit card across your nose. Click your left pupil, then right pupil, then the left and right card edges. PD is calculated automatically using the card as a scale.
Upload a clear, front-facing photo with a credit card held at eye level.
Your Pupillary Distance
