Near PD for Reading Glasses
The pupillary distance for reading glasses is called near PD. Your eyes turn slightly toward each other when you read. Start from your distance PD; you will normally find that the near PD is about 3 mm smaller.
What are your two numbers?
Enter your PD and you'll see the number to use for reading glasses.
Near PD vs Distance PD
To measure distance PD, you look far away, and most orders want that number. Lenses meant only for near viewing use the near PD. A common method is to subtract 3 mm from your single PD, or 1.5 mm from each half of a dual PD (Warby Parker).
When You Need a Near PD
Single vision reading glasses and some computer glasses set for close work call for it. Your distance PD goes on progressive and bifocal lenses, and the lab places the reading area on its own. Reading segments on lined bifocals need to be placed no farther than 2.5 mm from the near PD (ANSI Z80.1).
How to Calculate Near PD
Subtract 3 from your distance PD: a PD of 63 mm becomes a near PD of 60 mm. A prescription that already lists two values roughly 3 mm apart, for example 64/61, gives you the near PD as the second value.
| Distance PD | Near PD, estimate | Each eye, near |
|---|---|---|
| 56 mm | 53 mm | 26.5 mm |
| 58 mm | 55 mm | 27.5 mm |
| 60 mm | 57 mm | 28.5 mm |
| 62 mm | 59 mm | 29.5 mm |
| 63 mm | 60 mm | 30 mm |
| 64 mm | 61 mm | 30.5 mm |
| 66 mm | 63 mm | 31.5 mm |
| 68 mm | 65 mm | 32.5 mm |
| 70 mm | 67 mm | 33.5 mm |
| 72 mm | 69 mm | 34.5 mm |
Near PD Questions
Does PD still matter with reading glasses?
Yes. With reading glasses made at your distance PD, the lens centres sit a little outside where your eyes point when you read.
Which PD should I use for computer glasses?
Most people use the distance PD for a screen kept at arm's length. Use the near PD for glasses worn only at book distance.