You've just had your eyes tested and the optometrist hands you a slip covered in numbers and abbreviations. If you want to order prescription glasses online, you need to copy those numbers exactly. This guide explains each value in plain language, so you can read your prescription with confidence. It won't tell you what your eyesight "should" be. That's your optometrist's job.
Right eye or left eye? OD and OS
Most prescriptions in India have two rows, one per eye:
- OD (oculus dexter), or R: your right eye.
- OS (oculus sinister), or L: your left eye.
- OU sometimes appears too. It means both eyes.
Mixing up the two rows is the most common mistake when ordering online, and it swaps your lenses. Always match the row label, not its position on the page.
SPH (Sphere): the main power
SPH is the main lens power, in dioptres. The sign is the important part:
- Minus (−), e.g. −1.25: a lens for distance vision (short-sightedness / myopia).
- Plus (+), e.g. +1.50: a lens for near vision (long-sightedness / hyperopia).
Powers usually go in steps of 0.25: −0.25, −0.50, −0.75 and so on. If the SPH box says PL or Plano, the power is zero.
CYL (Cylinder) and AXIS: correcting astigmatism
CYL is an extra power used to correct astigmatism. It can be minus or plus, and it is also written in 0.25 steps.
AXIS is a direction, written as a whole number from 0 to 180 degrees. It tells the lab which way to turn the cylinder power in the lens.
CYL and AXIS always come as a pair. If your prescription has a CYL value, it will have an AXIS too. If the CYL box is empty or says "DS" (spherical only), leave both blank.
ADD: extra power for reading
ADD appears on bifocal and progressive prescriptions, usually for people over 40. It is the extra plus power added to the lower part of the lens for reading, typically between +0.75 and +3.00. If you only need single-vision glasses, you won't have an ADD.
Some slips write the reading power as a separate "NV" (near vision) row instead. If yours looks like that, send us a photo and we'll read it with you.
PD (Pupillary Distance)
PD is the distance between the centres of your pupils, in millimetres. Most adults fall between about 54 and 74 mm. It is written either as one number (e.g. 63) or as two (e.g. 31.5 / 31.5, one per eye). PD makes sure the optical centre of each lens sits in front of your eye.
PD isn't always printed on the slip. If yours doesn't have it, leave it blank when ordering from EYVRO and we'll confirm it with you before the lenses are cut.
A worked example
| Eye | SPH | CYL | AXIS | ADD |
|---|---|---|---|---|
| Right (OD) | −1.75 | −0.50 | 180 | — |
| Left (OS) | −2.00 | — | — | — |
This reads as: the right eye needs −1.75 main power, with −0.50 cylinder at axis 180. The left eye needs −2.00 with no cylinder. There is no ADD, so single-vision lenses are right.
Common mistakes to avoid
- Dropping the sign. −1.50 and +1.50 are completely different lenses. Copy the + or − exactly.
- Swapping the eyes. Read the OD/OS (R/L) labels, not the row order.
- A CYL without an AXIS. The lens can't be made without both.
- Using an old prescription. If you're squinting with your current glasses, get re-tested before ordering.
Ordering prescription glasses from EYVRO
When you choose lenses on any frame, you can upload a photo of your prescription, type the values in, or send it after ordering. Our opticians check every prescription before cutting the lenses, and anything unclear is confirmed with you first. Our standard lenses cover Power up to -6.00 / +2.00 SPH, -2.00 / +2.00 CYL. Stronger powers are still made as a special order.
Need a hand? Talk to us
EYVRO is the online brand of Deepak Opticals, Aligarh (opp. Gandhi Eye Hospital, Ramghat Road). If anything on your prescription or frame is unclear, send us a photo on WhatsApp and our opticians will tell you what they see, or visit the store for an eye test and fitting. You can also read our prescription help page or browse eyeglasses and add your prescription at checkout.
