Measure your pupillary distance (PD)
Pupillary distance (or PD) refers to the distance between your two pupils. It’s necessary to center a prescription in your frames for clear, accurate vision.
You can use our online tool here to measure your PD using just a photo.
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Take a frontal face photo that you holding a credit card-sized plastic or paper under your nose as demonstrated in the following image.
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Upload the photo, then zoom in the photo and place the center of the sight in your pupil.
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Zoom out and drag the image so that the card is finally placed exactly where the fake card is, then push done button.