PUPILLARY DISTANCE
PD+ instantly measures pupillary distance (PD) by capturing & processing a single, hi-res facial photo. Measurement accuracy is guaranteed to be the highest achievable by the capability of your device's camera system. Far and near PD's -- binocular & monocular -- are always available at no cost.

SEG HEIGHT
PD+ instantly measures Segment Height -- Seg Height -- for the frames you are currently wearing. Accurate seg height and PD measurements are needed to ensure that lenses being made for your frames are properly centered on your eyes to achieve optimal viewing clarity. Please note: Seg Height is currently only supported on devices equipped with the TrueDepth or LIDAR camera systems (e.g., iPhone X and later non-SE models).

CALCULATORS
- Rx Transposition
- Vertex Adjustment
- Crossed Cylinders (over-refraction)
- Keratometry Conversion
- Visual Acuity Scale
- Estimated visual acuity
- Minimum Blank Size (MBS)
- Simple Magnifier and Spectacle Magnifications