How We Measure

How We Measure
Sizing in millimeters—so your fit feels intentional.


All BAPORSSA sunglasses are sized in millimeters (mm). You will usually find the same size code on the inside of the temples or on the product card, which indicates the lens width, bridge width, and temple length.

Read the numbers

1) Read the size code
You may see a format like 53 – 20 – 147.

  • 53 = Lens width (one lens)
  • 20 = Bridge width (distance between lenses)
  • 147 = Temple length (arm length)

Tip: If you already own a pair that fits well, compare these numbers first—they’re the fastest way to predict fit.

Core size definition

2) What each measurement means (mm)

Lens Width (A):
Measured across the widest horizontal point of one lens. Larger numbers generally mean more coverage.

Lens Height (B):
Measured vertically at the tallest point of the lens. Useful for understanding coverage and “shield” feel.

Bridge Width (DBL):
The distance between the lenses at the bridge area—this affects how the frame sits on your nose.

Temple Length:
Measured from the hinge to the end tip of the arm (some methods measure hinge→bend + bend→tip). It influences ear comfort and stability.

Front / Frame Width (Endpiece-to-Endpiece):
The total width across the front. This is the best “at-a-glance” indicator of whether a frame will feel narrow/regular/wide on your face.

Our measuring method

3) Our measuring method
We follow the industry’s “boxed lens” measurement logic: lens dimensions are taken from a rectangle that tangentially encloses the lens shape (often called the boxing system). This helps keep sizing consistent across different lens silhouettes.

Note: Small tolerances can occur due to finishing and material behavior—especially across different styles and constructions.

Self-Testing

4) Measure at home in 60 seconds

Option A — Use your best-fitting glasses

  1. Look inside the temple arm for the numbers (e.g., 53 - 20 -147)
  2. Match those three numbers to the product you’re viewing
  3. If you’re between sizes, prioritize frame width and bridge first

Option B — Use a ruler (mm) on your current pair

  • Lens width: widest horizontal point
  • Bridge width: shortest distance between lenses
  • Temple: hinge to tip (or hinge→bend + bend→tip)

Fit guidance

5) Quick fit guidance

  • If your frames slide down: you may need a smaller bridge or more stable front width.
  • If your temples feel tight: consider a wider front (endpiece-to-endpiece).
  • If the frame leaves marks on the nose: the bridge may be too narrow.