How to Read Temple Size Markings
Many frames carry a short size string such as 52-18-140 (on the frame itself a small square usually stands between the first two numbers instead of the first dash). All three numbers are millimeters, and this catalog stores them as three separate fields.
The three numbers
| Position | Example | Catalog field | Meaning |
|---|---|---|---|
| First | 52 | lens_width_mm |
Horizontal width of one lens |
| Second (after the square) | 18 | bridge_width_mm |
Distance between the lenses at the bridge |
| Third | 140 | temple_length_mm |
Length of the arm |
The square symbol only separates lens width from bridge width. Some pages write the same thing as 52-18-140 or give just the first two numbers, for example 52-22.
Where the numbers appear
On a physical frame the marking is usually printed on the inside of a temple arm, often next to a model code and a color code. Online, the numbers may show up in a page title, a size selector or a measurements table. The catalog records where each value came from. For example, the size of a Ray-Ban Original Wayfarer Classic RB2140F variant was read from the page title "(52-22)" (Ray-Ban US). The maker page did not state a temple length, so that field stays unknown in the catalog rather than being borrowed from another size or listing.
When a page leaves out a number, the field stays null. The catalog never fills it in from a similar frame.
Why a size does not identify a model
Different models can share the same size. Each of these Ray-Ban pages lists 54-18:
- Original Wayfarer Classic RB2140 (Ray-Ban US)
- Original Wayfarer Classic RB2140F (Ray-Ban US)
- Erika Classic RB4171 (Ray-Ban US)
Size letters don't identify a model either. Oakley's US pages show the label "XL (140mm)" for both the Holbrook OO9102 (Oakley) and the Holbrook XL OO9417 (Oakley).
To pin down a product, use the size together with the style code (such as RB2140F or OO9102) and the color or variant code. The size by itself is not enough.
What the numbers do not tell you
These numbers describe the frame. They don't tell you whether it will fit a particular face, and this site gives no fit guarantees.