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How to measure your pupillary distance (PD).
Pupillary distance measures the distance between your pupils. It's a crucial measurement for ensuring that your eyewear is properly aligned to your eyes.
If it's not included in your prescription, you can visit AccuPD, a free tool that measures your PD.
However, to obtain the most accurate PD reading, a Call or Visit to your Dr. would be advised.
If you prefer, you can also measure your PD yourself following the steps below with a ruler and mirror. It's important to measure from the center of one pupil to the center of the other.
1. Stand 8–12 inches away from a mirror.
2. Hold a ruler against your brow or cheekbones.
3. Close your right eye and align the ruler end with the center of your left pupil.
4. Look straight ahead, close your left eye, and open your right eye. Note the measurement to the center of your right pupil.
However, to obtain the most accurate PD reading, a Call or Visit to your Dr. would be advised.
If you prefer, you can also measure your PD yourself following the steps below with a ruler and mirror. It's important to measure from the center of one pupil to the center of the other.
1. Stand 8–12 inches away from a mirror.
2. Hold a ruler against your brow or cheekbones.
3. Close your right eye and align the ruler end with the center of your left pupil.
4. Look straight ahead, close your left eye, and open your right eye. Note the measurement to the center of your right pupil.
- PD is measured in mm and can be one number like 64 or two numbers like 31/33.
- The first number in a two number PD is the Right or OD.
- Getting the two-number PD is always the best choice when creating custom-made eyewear as it centers each Rx in front of each eye, versus the less accurate method of dividing the single number by two.