How to Measure Your Pupillary Distance (PD) Yourself?

How to Measure Your Pupillary Distance (PD) Yourself?

Pupillary Distance (PD) is an essential measurement when making glasses, ensuring that the focal point of the lenses aligns with the centers of your pupils. This alignment directly affects visual clarity, especially for those with stronger prescriptions. Having an accurate PD helps in crafting lenses that offer optimal clarity.

You can have your PD measured at an optometrist or optical store. Typically, you’ll find this value labeled as "PD" on your prescription or vision test results. However, if you’re unable to visit an eye clinic or store, here are two easy methods to measure your PD at home.

Both methods result in 66 mm

Method 1 (Recommended): Measure PD Using a Mirror – Takes Only 30 Seconds!

What you need: A mirror mounted on a vertical wall and a ruler with clear millimeter markings (1 cm = 10 mm).

1. Stand in front of the mirror with your head straight (avoiding forward or backward tilting).
2. Hold the ruler horizontally against the lower edge of your eyes, ensuring it’s straight without any bend.
3. Align the 0 mm mark of the ruler with the center of one pupil (for example, your left eye) while focusing on that eye.
4. Shift your focus to the center of your other pupil (right eye) and note the millimeter mark that aligns with it. This is your PD.
5. For accuracy, repeat the measurement two to three times.

Method 2: Measure PD Using a Camera

What you need: A friend, a digital camera, and a ruler with clear millimeter markings.

1. Have your friend stand at least 2 meters in front of you, holding the ruler horizontally against the lower or upper edge of your eyes.
2. Keep your eyes focused straight ahead at a fixed point, with your head upright to avoid tilting, and ensure the ruler stays flat.
3. Your friend should take a close-up photo of your face, ensuring the camera is level with your eyes.
4. Zoom in on the photo, and use the ruler to measure the distance from the center of one pupil to the center of the other. This is your PD.

Important Notes:

• Measure a few times to ensure accuracy. In most cases, PD ranges between 50 mm and 75 mm, with 64 mm being the most common.
• Manual measurement may have slight errors, with typical variations within 3 mm.