Find your PD

Measure it online, easily.

Measure your pupillary distance (PD) in seconds...

But what is a pupillary distance?

In short, it’s the distance between the centres of your pupils (the black circles in the middle of the eyes).

Your PD is a key part of your glasses prescription that tells us the exact area of the lens you look through for clear vision.
It helps us fine-tune your lenses to your exact measurements.

Don’t see a PD on your prescription? Our simple tool will provide you with your accurate PD in seconds.


Pupillary distance is used to ensure that the power of the lenses will be in the optimum position for vision correction.

If your PD isn’t within the acceptable tolerance, you might experience eye strain, headaches, fatigue, and blurry vision. Having a high prescription and the wrong PD can make these symptoms worse, so we recommend getting the most accurate PD.

Our tool has a sensitivity of 2.5mm which means you will always have an accurate PD measurement.

You may have to find your own PD value if your optician did not include it on your prescription. A PD value is often required when ordering glasses online. Using an online, accurate tool like ours can help you save time on a trip to the opticians!

Your PD does not affect the size of your glasses frame; however, it can affect the shape of your lenses.

Before you start, get a standard magnetic card and turn the volume up on your device. Next, position yourself 30-40 cm from the screen and align your face parallel to the camera. Move away any loose hair so that your eyes are clearly visible, and remove your glasses. Hold the card at the top corner with its magnetic strip facing outwards, just above your eyebrows, and follow the voice instructions. You’ll have your PD in a minute!

Choose a light colored card with a magnetic strip. Hold it by the top corner, right above your eyebrows. There's no need to use a credit card (please don't). Drivers license, library card, club card — they all work great!

Our supported PD range is (44-80)mm, which covers up to 95% of the adult population.

Clean your desktop/phone camera
Use a standard, light colored magnetic card
Perform the scan in a well lit room, with no bright backlight
Check your network connection (and switch to WiFi if available)
Adjust the volume and listen to the instructions carefully

The PD calculation is proven accurate within a ±2.5 mm, which fits the industry standard. Remember, these results can vary between optometrists as well.
If the difference in the results is less than ±2.5 mm, we suggest using the average PD value.
If the difference is more than ±2.5 mm, please get in touch.

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