All Guides

Expert-level resources for buying prescription glasses online. Each guide is written by eyewear industry professionals with data-backed research.

Prescription Reading

SPH, CYL, AXIS, ADD, PD — what every number and abbreviation on your prescription means, with real examples.

Three methods to measure PD accurately, from ruler to app to online tool.

From prescription to checkout — everything you need, what's legally required, and how long it actually takes.

Frame cost, lens cost, coatings, shipping — a transparent breakdown.

Side-by-side comparison of the three main lens types.

Thinner, lighter lenses for stronger prescriptions — which one matches your prescription.

What the numbers on your temple arm mean, how to measure your face for glasses.

Prescription expiration rules differ by state. Here's the complete breakdown.

Do blue light glasses work? We reviewed 30+ peer-reviewed studies.