Specs Frame Size Chart: My Simple Breakdown

When I first looked at a specs frame size chart, I was confused by all the numbers and diagrams. Here's how I finally made sense of it all.

The Basic Three Numbers

Every pair of specs has three key measurements printed inside, like "52-18-140":

52 - Lens width in millimeters

18 - Bridge width in millimeters

140 - Temple length in millimeters

Why These Numbers Matter

Each measurement affects fit differently:

Lens width - Determines if frames look proportionate on your face

Bridge width - Affects comfort on your nose

Temple length - Ensures arms reach properly behind ears

How I Use Size Charts

My process is simple:

Find specs I own that fit well

Write down their three numbers

Look for new specs with similar measurements

Stay within 1-2mm of my ideal size

Common Size Ranges

Most specs fall into these categories:

Small: 48-50mm lens width

Medium: 51-54mm lens width

Large: 55mm+ lens width

My Key Takeaway

Once I understood what the numbers mean, size charts became incredibly useful. They're not complicated - just three simple measurements that ensure proper fit.