LensCrunch

Optical calculators for lenses, frames and prescriptions

Free, no signup, no email wall. Every tool shows the maths behind the answer, so you can check it yourself.

Lens Thickness Calculator & Visualizer
How thick will your glasses actually be? Compare CR-39, Trivex, polycarbonate, 1.60, 1.67 and 1.74 high-index by edge thickness, center thickness and weight — with a to-scale cross-section.
Prescription · Frame size · PD → thickness
High-Index Lens Comparison: 1.50 vs 1.60 vs 1.67 vs 1.74
Thickness, weight and Abbe value for your own prescription — plus the optical-quality trade nobody mentions when they sell you 1.74.
Prescription → thickness · weight · Abbe value
Frame Size & Fit Calculator
Will a 52□18 actually fit your face? Get the eyesize, bridge and temple range to shop in, check any specific frame, and see what its size does to your lens thickness.
Frame measurements · face width · PD
PD Ruler (printable) & PD Converter
Print a true-scale ruler with a bank-card calibration bar, measure your pupillary distance in a mirror, and convert between single (binocular) and dual (monocular) PD. Includes typical PD values for adults and children.
Printable ruler · on-screen ruler · single ↔ dual PD
1.67 vs 1.74 High-Index: What You Actually Get
The upgrade that costs the most and delivers the least, calculated for your prescription — plus the frame-size effect that moves your thickness about seven times more.
Prescription → millimetres · frame leverage

For opticians

The free tools above stay free. This one is a paid tool, for the part of the job that is a business document rather than a calculation.

LensCrunch Pro — Dispensing Report Builder
A prescription, a frame and your own price list go in; a branded A4 report you can hand to the customer comes out, plus a shop copy with cost and margin for each material. One 55 KB file that runs offline — no account, no subscription, no per-report charge.
US$29 one-time · Windows · macOS · Linux

Not medical advice. LensCrunch performs optical geometry. It does not measure, diagnose or correct vision. Follow your optometrist's or optician's advice for anything clinical.

Questions, corrections or requests: hello@lenscrunch.com

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