Low, Medium, and High Add of Multifocal Contact Lenses

What does ADD mean on a contact lens prescription?

ADD is the near addition — the extra plus power a multifocal lens provides for near vision, relative to its distance power.

It appears only on multifocal and bifocal designs. A single-vision order has no add field, and a blank one usually means a single-vision lens rather than a missing value.

It prints in one of two forms. Some prescriptions carry a dioptric value, written like any other power. Others carry a written designation — LOW, MED, HIGH, or a manufacturer's equivalent wording. Both are complete prescriptions. The field-by-field walk through a printed label is on how to read the printed label; the sphere it sits beside is on is power the same as sphere.

Why multifocals are ordered in LOW, MED and HIGH bands

Because a multifocal contact lens is a whole optical geometry, not a distance lens with a near number added to it.

A progressive spectacle lens can carry an arbitrary add because the near zone is a physically separate region of a large lens, and the eye moves to it. A contact lens moves with the eye. Its distance and near powers have to coexist across a small optic that sits over the pupil at all times, distributed in concentric zones or a gradient. Changing the add therefore does not mean adding plus to one region — it means selecting a different power profile across the whole optic.

The designation names which of a design's profiles is being ordered. Three consequences follow, and they are the reason this page exists:

• A band is not a diopter value. LOW does not decode to a specific add. It identifies a profile whose near performance sits at the low end of that design's range.
• A band is not portable between designs. One manufacturer's MED and another's MED are two different optics, because each was drawn against its own distance-to-near distribution. A patient moved between designs at the same designation has not been kept on the same correction.
• The bands are few. A near add can be refracted in 0.25 D steps; a design offers a small number of profiles. The refracted add does not land on a band, it points at one.

How a spectacle near add maps onto a band

The spectacle near add informs which band to start in. It is not carried across as a number.

Two things happen before the add is considered at all. The distance sphere is converted to the corneal plane — a spectacle sphere is not the ordered contact lens power above the vertex gate, which is the subject of is power the same as sphere and the Contact Lens Conversion Calculator. And the refraction itself is taken conservatively: published fitting guidance is a least minus, least add refraction rather than the most plus a patient will accept at near.

From there the spectacle add sets the starting band, and the published guidance is to start low. Eyes On Eyecare's presbyopic fitting guide begins with the lowest add and stays conservative with plus, on the grounds that a multifocal delivers functional vision for daily tasks rather than glasses-level near — and that expectation is set before the trial, not after it. Review of Contact Lenses makes the complementary point: modern designs do not follow the old shortcut of raising the add for every near complaint.

What band a given spectacle add points at is a property of the design being fitted, and it is read from that design's own guidance. This site is manufacturer-agnostic and does not publish those mappings.

“Add power by age” is a spectacle number

Searches for an add power by age rarely mean contact lenses at all.

That phrasing belongs to spectacle presbyopia — reading-add-by-age conventions used when writing a near addition for glasses, in a body of material that is entirely spectacle lens design and carries no corneal-plane conversion anywhere in it.

It is named here once so it can be told apart from this field, and then dropped. An age is not an input to a contact lens add designation. The inputs are the refraction, the design being fitted, and what the patient sees through the trial lens.

Where the starting-add procedure lives

Not here. The Multifocal Contact Lens Calculator owns it.

That page converts distance power at the corneal plane, returns equal-add starting parameters, and carries the sequence that follows: eye dominance, letting the lens settle, binocular over-refraction on real-world tasks, and changing one parameter at a time. Unequal adds and a distance-lens-plus-multifocal arrangement are endpoints of that process, not starting points.

This page stops at the point that page begins — what the designation is, and what it is not. Verify the result with an over-refraction once a trial lens has settled.

Starting contact lens parameters still require on-eye fit

An add band is a starting parameter, not a prescription.

It is chosen from a refraction and a design's guidance, before anyone has seen what the lens does on the eye. Whether the distribution suits that patient's pupil, dominance and daily tasks is visible only after the lens settles and is over-refracted binocularly.

Read Starting Contact Lens Parameters Are Not a Prescription for the bound that applies across this site. Convert spectacle prescription to contact lens parameters for power. Fit a starting multifocal contact lens on eye. Verify with over-refraction after the trial lens. Contact lens parameters at the corneal plane stay unfinished until that sequence is done.

Sources

Clinical claims on this page are attributed to the publications below.

• Pal, Review of Contact Lenses, Do You Follow These Fitting Principles? (November 2018) — a least minus, least add refraction as the starting point; modern multifocal designs do not follow the old shortcut of raising the add for every near complaint. Attributed identically on the Multifocal Contact Lens Calculator.
• Hay, Eyes On Eyecare, Guide to Fitting Contact Lenses for the Presbyopic Population (15 May 2017) — start with equal adds after an accurate refraction; begin with the lowest add and stay conservative with plus; multifocals give functional distance and near rather than glasses-level clarity.