Skip to main content

​
Reading glasses or computer glasses - which do you need?

By Spektrum Glasses Editorial Team · Published 2026-08-10 · Updated 2026-09-11 · Facts re-checked 2026-09-11 How this page is written and checked: our editorial method · how we verify claims

​
Short answer

Reading glasses and computer glasses are usually the same single-vision lens sold at different strengths, not different optics. A single-vision lens has one focal distance, and reading sits closer than a screen, so pick the strength for whichever distance you use most and check the lens’s coatings and lab-measured transmittance, not just its diopter or price.
  • Reading and computer glasses are usually the same single-vision lens at different strengths.
  • One lens has one focal distance; reading and screen distances are not the same.
  • Choose the strength for the distance you use most, not by the product label.
  • ANSI Z80.3 tests light transmittance and color, not magnification accuracy - check both.
  • Single-vision lenses do not correct astigmatism or replace an eye exam.

​
Reading glasses and computer glasses are usually one lens, not two products

Non-prescription “reading glasses” and “computer glasses” almost always use the same single-vision lens design: a lens ground to one fixed power, set into a frame, with no correction for astigmatism and no way to shift focus as the wearer moves between distances. What usually changes between a “reading” label and a “computer” label is the power itself - the diopter, typically written as +0.50 through roughly +3.00 - and the marketing story around it, not the underlying optics. A single-vision lens is specified for one working distance. Move closer or farther than that distance and the image blurs, because the lens cannot refocus the way a natural eye, or a multifocal prescription lens, can. That is true of any non-prescription reader, regardless of brand - it is a property of single-vision optics, not something a manufacturer can engineer around. So the more accurate version of the question is not “which product do I need,” it is “which distance am I correcting for” - because a printed page and a monitor are rarely the same distance from the eye.

​
Choose by distance, not by the label on the box

Reading distance - a book or phone held in the hand - is closer than screen distance, where a monitor typically sits at arm’s length or farther. A single-vision lens ground for one of those distances is, by definition, a compromise at the other; no non-prescription lens is correctly focused at a close page and a farther screen at the same time. The practical answer is to choose the power for the distance spent the most time at, and accept the other distance as the compromise. If most of the day is spent at a screen, buy for the screen; if most of the day is spent on print, buy for print. Power should be matched to the distance and to comfort at that distance - do not assume a lower power is automatically the safer “computer” choice; that assumption does not hold up as a general rule. Because the right power depends on the person and the distance, non-prescription readers are usually offered across a range of strengths rather than one fixed power. Our own range runs +0.50 to +3.00 across nine strengths in the core style, and some frames are also sold with no magnification at all, in the same coatings and tint, for wearers who do not need added power.

​
The checks that go beyond strength and price

Two lenses carrying the same “+2.00” label, or the same blue-light claim on the packaging, are not necessarily the same lens. These are the checks that separate a specified lens from a ready-made magnifier, on any brand, not just this one:
  • Coatings. Anti-reflective coating on both lens faces cuts the glare that washes out small print and screen text; a lens with no coating, or coating on one face only, behaves differently even at an identical diopter.
  • Spectral transmittance, by wavelength band. A “blocks blue light” claim with no wavelength range attached cannot be checked against anything. A published transmittance curve, measured across specific nanometer bands, can be.
  • Visible light transmission (VLT). This is what tells you whether a lens reads as clear or as a visible tint, which matters because a heavy tint changes how true colors look on a page or a screen.
  • Chromaticity and color accuracy. ANSI Z80.3 testing covers how a lens transmits light and holds color - it does not test how accurately the lens’s reading power is ground. A lens can pass Z80.3 transmittance and chromaticity testing and still be over- or under-plussed at a given strength; those are two separate claims and are worth checking separately.
  • Lab accreditation. A transmittance report from a laboratory accredited to ISO/IEC 17025 (for example, by A2LA) is a checkable, third-party number. A percentage printed on a listing page with no report behind it is not.

​
Reading our own numbers through the same checks

Passing those checks on our own clear lens (COLTS Laboratories report O-SPG111015, tested by a laboratory accredited to ISO/IEC 17025, certificate 1612.01, spectral transmittance measured per ANSI Z80.3):
  • Blue-light filtering by band: 99.99% filtered at 400nm, 95.1% at 410nm, 63.0% at 420nm, and 33.1% at 450nm. The drop-off across that range is the point - a single “blocks 99%” headline would hide that the filtering falls off sharply by wavelength, which is why the band has to travel with the number.
  • Visible (photopic) light transmission: 91.6%, which is why the lens reads as near-clear rather than a visible tint, on paper and on a screen.
  • UVA and UVB: both filtered above 99.99%.
  • ANSI Z80.3 transmittance and chromaticity: a pass on all samples in the clear lens group, filter category 0, cosmetic lens. As above, that standard covers light transmittance and color, not the accuracy of the reading power itself - a Z80.3 pass says nothing about whether a given diopter is ground correctly.
  • The reading power sits in the same coated lens used across the non-reading version of a frame, so these numbers hold at every strength, not just one.
Clear is not one specification, either: our ZENOX clear lens averages about 52% filtered across the same 400-500nm blue band while filtering close to 100% of UV - a different curve from the O-SPG111015 clear lens above, despite both reading as colorless to the eye. Independent research on commercially available blue-light-filtering lenses has found meaningful variation across the market: one 2017 peer-reviewed study measured a roughly 10-24% reduction in calculated blue-light hazard across a set of commercial lenses (Leung, Li & Kee, “Blue-light filtering spectacle lenses: optical and clinical performances,” PLOS ONE). That range is a case for reading a lens’s own report rather than treating “blue light glasses” as one uniform category.

​
What no single-vision lens can do

A single-vision reading or computer lens, non-prescription, has one job: shift focus for one distance. It does not correct astigmatism, which requires a cylindrical or toric correction ground into the lens; a wearer with astigmatism will not get a sharp image from a spherical reading power, regardless of brand or strength chosen. It also does not replace an eye exam - it cannot diagnose a change in prescription or an eye health issue, only whether a given power makes near text look sharper right now. If reading or screen use stays uncomfortable even with a well-chosen non-prescription power, that is a reason to see an eye care professional, not to try another non-prescription strength.

​
Where these numbers come from

Every measured figure quoted here is transcribed from a third-party laboratory report, published in full with the wavelength band and the report number: lab results. Our rule for what may appear on this page at all is on how we choose what to publish.

​
A PROSPEK style for this

Buy on Amazon — $39.95

Ships from Amazon (Prime, 30-day returns). Sold by PROSPEK by Spektrum Glasses.