LENSOPT
See clearly — plain-English eyewear guides, lens science, and the optical calculators every glasses and contact-lens wearer needs.
From measuring your pupillary distance and converting a prescription between glasses and contacts to sizing a frame, estimating lens thickness, decoding a sunglass tint, and costing your lenses, LensOpt pairs free hands-on optical calculators with plain-English guides and a richly illustrated museum of eyewear. Understand your glasses, buy the right pair, and see clearly.
Eyewear Tools & Calculators
Free tools for every glasses and contact-lens decision — pupillary distance, vertex distance power conversion, frame size and fit, lens thickness, sunglass tint category, and contact-lens cost-per-wear.
Pupillary Distance (PD) Calculator
Convert between per-eye and both-eyes PD, and estimate the near PD your reading glasses need.
Vertex Distance Power Converter
Move a prescription between glasses and contacts and see how the vertex gap changes the power.
Frame Size & Fit Calculator
Read the eye-size, bridge, and temple numbers off a frame, add your PD, and see whether it fits.
Lens Thickness Estimator
See how power, material, and frame size drive lens thickness — and what a higher index really saves.
Sunglass Tint & UV Category Finder
Turn a light-transmission percentage into a filter category and know where a tint is safe to wear.
Contact Lens Cost-per-Wear Calculator
Work out what your contacts cost per day worn, and compare dailies against monthlies fairly.
Eyewear & Optics Museum
Wander an illustrated museum of eyewear and optics — the frame styles and materials from the pince-nez and monocle to modern acetate and titanium, the corrective lenses and coatings that focus light, the anatomy of the human eye, and the instruments and professions of vision care, each in its own gallery. Every entry, image, and fact is drawn from Wikipedia and Wikimedia Commons.
Tour the museum →From the Journal
Fresh guides on choosing glasses and frames, reading a prescription, lens materials and coatings, contact lenses, sunglasses and UV, and everyday eye care and eyewear know-how.
The Science Behind Myopia Control: Understanding Causes, Prevention, and Modern Solutions
Silicone Hydrogel: Revolutionizing Contact Lenses and Medical Innovations
The Ultimate Daily Disposable Lens Experience: Why Convenience Meets Clarity Every Day
The Science Behind Polarized Lenses: How They Transform Your Visual Experience
The Invisible Hazard: Understanding Blue Light’s Impact on Your Vision and Health
The Science Behind Lens Coatings: Enhancing Clarity and Durability for Optimal Vision
Keep Learning
Plain-language explainers on reading your prescription, how the eye focuses, frames and fitting, lens materials and coatings, and everyday eye health — everything you need to understand your eyewear and choose it with confidence.
Visit the Learn hub →