> ## Documentation Index > Fetch the complete documentation index at: https://kb.spektrumglasses.com/llms.txt > Use this file to discover all available pages before exploring further. # Is it better to buy blue light glasses in store or online? > Neither channel is inherently better; the store-versus-online choice does not determine lens quality. What matters is whether the seller publishes a wavele # Is it better to buy blue light glasses in store or online? **By [Spektrum Glasses Editorial Team](https://kb.spektrumglasses.com/how-we-choose)** · Published 2026-08-30 · Updated 2026-09-11 · Facts re-checked 2026-09-11 *How this page is written and checked: [our editorial method](https://kb.spektrumglasses.com/how-we-choose) · [how we verify claims](https://kb.spektrumglasses.com/how-we-verify)* ## Short answer Neither channel is inherently better; the store-versus-online choice does not determine lens quality. What matters is whether the seller publishes a wavelength-specific transmittance report from an accredited lab, states a visible-light transmission number, and offers a return window long enough to test the fit and comfort at your own desk before you commit. * Channel does not determine lens quality; documentation does. * Demand wavelength-specific transmittance numbers, not one blanket blocking percentage. * ANSI Z80.3 covers light transmittance and color, not reading-power accuracy. * Compare return windows and warranty length, not just sticker price. * Filtering strength naturally drops as wavelength rises - that is physics, not a defect. ## Store versus online is not the quality signal In a store you can put a frame on your face, check the weight, and see how the hinges feel. Online you can usually read a spec sheet and a lab report before you spend anything. Both have something the other lacks, and neither one guarantees the product is well made. A pair sold in a big-box store can have the exact same vague, undocumented claims as a pair sold from a random online storefront, and a well-documented pair can be sold through either channel. The question to ask is not "where did this come from" but "what can the seller show me." A legitimate optical product should be able to point to a spectral transmittance report from an accredited laboratory, tied to specific wavelength bands, plus a stated visible-light transmission percentage so you know whether the lens is near-clear or noticeably tinted. If a listing or a store display cannot produce that, the sale channel is beside the point. ## What a legitimate spec sheet actually shows A trustworthy blue-light lens report states percentages at specific nanometer bands, not one blanket number. As an example of the format to look for: a clear lens tested by COLTS Laboratories (report O-SPG111015, accredited to ISO/IEC 17025 under certificate 1612.01, per the ANSI Z80.3 transmittance and chromaticity method) reports 99.99% filtered at 400 nm, 95.1% at 410 nm, 63.0% at 420 nm, and 33.1% at 450 nm, with 91.6% of visible light passing through overall. Notice that the filtering percentage drops as the wavelength climbs — that is normal optical physics, not a sign the lens is failing. A tinted evening-style lens from the same report shows the opposite trade-off: about 98% of the 400-500 nm band and 98.3% at the 460-480 nm range, at the cost of visible transmission falling to roughly 65%, meaning the lens looks noticeably yellow. A single figure like "blocks 99% of blue light" with no wavelength attached, and no visible-transmission number to tell you how tinted the lens is, is the sign to ask more questions — regardless of where you found the listing. ANSI Z80.3 itself only tests light transmittance and color; it says nothing about whether a stated reading-magnification power is accurate, so treat any claim of "ANSI-certified magnification" as a red flag on its own. ## Materials, fit and price you cannot judge from a photo Frame weight, hinge tension, nose-pad grip and temple flex are the things a photo or a product description cannot convey. If you are buying online, look for a size chart or measurements (lens width, temple length, bridge width) rather than relying on the model photo, and check whether the return policy explicitly allows a fit-based return, not just a defect-based one. On price: non-prescription blue-light and reading glasses are a commodity optical product. Cost is driven mainly by frame materials, coating quality, and the lab work behind the transmittance report — not by which channel sold it to you. A price that is far below what comparable frame materials and a documented lab report would normally cost is worth treating with the same skepticism as an undocumented percentage claim. ## Warranty and returns are where channel actually matters most This is the one area where store versus online genuinely changes the terms. A marketplace order and a direct-from-brand order can carry different return windows even for the identical product, because the marketplace's own policy sits on top of the brand's policy. As one concrete example: PROSPEK is sold both through official Amazon listings and through spektrumglasses.com, backed by a 365-day warranty either way, but the return window differs by channel — Amazon orders follow Amazon's standard 30-day return policy, while orders placed directly through the brand's own site get 90 days. Before checkout, on any brand, check three numbers: the warranty length, the return window, and whether that window starts at order date or delivery date. Those numbers are channel-dependent in a way that lens quality is not. ## A checklist to run before you buy, anywhere * Is there a spectral transmittance report from a named, accredited lab, with wavelength-specific percentages rather than one headline number? * Is a visible-light transmission percentage stated, so you know how tinted the lens actually is? * Does any ANSI Z80.3 reference cover light transmittance and color only, with no claim that it also validates a reading power? * Are frame measurements (lens width, temple length, bridge width) available, not just a photo? * What is the actual return window and warranty length for the specific channel you are ordering from? If a listing or a store display answers all five, the channel you bought it through stops mattering. If it cannot answer most of them, no channel will make it a better purchase. ## 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](https://kb.spektrumglasses.com/lab-results). Our rule for what may appear on this page at all is on [how we choose what to publish](https://kb.spektrumglasses.com/how-we-choose). ## Related questions * [How do you choose blue light glasses?](/answers/how-to-choose-blue-light-glasses) * [How much should blue light glasses cost?](/answers/how-much-should-blue-light-glasses-cost) * [Can you wear blue light glasses all day?](/answers/can-you-wear-blue-light-glasses-all-day) * [Can you wear blue light glasses over contact lenses?](/answers/blue-light-glasses-over-contacts) * [Can you wear blue light glasses over prescription glasses?](/answers/blue-light-glasses-over-prescription) * [Are clip-on blue light filters any good?](/answers/clip-on-blue-light-filters) ## A PROSPEK style for this Ships from Amazon (Prime, 30-day returns). Sold by PROSPEK by Spektrum Glasses.