Ever stared at the tiny numbers on your glasses’ temple arms and wondered what they mean? You’re not alone—most people skip over these digits, but they hold the key to finding glasses that fit perfectly (no more pinched noses, digging earpieces, or frames that overwhelm your face!).
You’ll find frame specs on the inner temple arms or demo lenses of most glasses. Let’s use a real example—Made In Japan 56□18—140 G18K—to decode what each part tells you:
- 56 (Lens Width, mm): The horizontal diameter of one lens (the widest part of the frame). This is the most important number for fit—too wide, and frames will swamp your face; too narrow, and they’ll look tiny.
- 18 (Bridge Width, mm): The shortest distance between the two lenses (aka “nose bridge width”). A bridge that’s too narrow pinches; too wide slips down your nose.
- 140 (Temple Length, mm): The total length of the temple arm from the frame front to the tip (measured when fully extended). Short arms dig into ears; long arms feel loose.
- □ or —: Just a standard separator—nothing to overthink!
Those extra letters/numbers (like Ti - P or 18K) aren’t just marketing—they tell you what your frame is made of:
- Titanium/Ti - P/TITAN: Full titanium frame (except nose pads, hinges, and screws). Light, hypoallergenic, and durable—but pricey.
- Ti - C: Partial titanium (only part of the frame uses it). Cheaper than full titanium but still strong.
- 18K/750: 18 - karat gold (75% pure gold). Pure gold is too soft for daily wear, so alloys are added—great for luxury lovers who want durability with a premium feel.
Fit beats fashion every time—here’s how to use these numbers to find your perfect pair:
The first number (e.g., 56) dictates how frames look on your face. Use this guide:
- Petite faces (46–51mm): Go for slim, compact frames—they won’t overpower small features. One friend with a tiny face wears 46mm lenses daily and says they “feel like they were made for her.”
- Average faces (52–55mm): Most people in the U.S. fall here—this range works for 80% of shoppers (we tend to have slightly larger faces than Japan/Korea).
- Large/wide faces (56mm+): Extra - wide frames are your friend. Pro tip for women: Bigger frames can make your face look smaller—try it, you’ll be surprised!
- Bridge Width: Match it to your nose—narrow bridges pinch, wide ones slip. If you have a high bridge, look for wider widths; if low, stick to narrower.
- Temple Length: Test by putting on frames—arms should wrap comfortably around your ears without digging in. Too short? They’ll pull; too long? They’ll slip.
Cut through the jargon—here’s how to pick based on your needs:
Luxury pick—super light, hypoallergenic, and long - lasting. Best for daily wearers who want premium quality (but it’s expensive and hard to adjust).
Titanium alloy—flexible (pure titanium is stiff!) and cheaper. Great for anyone who loves titanium’s feel without the price tag.
Fashion favorite—plant - based plastic that’s durable, colorfast, and hypoallergenic. Trendsetters and sensitive - skin wearers love it (many influencers wear acetate frames as accessories, not just glasses).
Active lifestyle pick—shatterproof, flexible, and lightweight. Perfect for kids, hikers, or anyone prone to dropping glasses.
Trendy but heavy—good for geometric designs, but avoid if you have a strong prescription (thick lenses make them even heavier).
Affordable and sturdy—great for casual wear or switching frames often (just know they’ll scratch/bend faster).
Brands love marketing “ultra - light” frames, but lenses are the heaviest part of your glasses. Here’s what actually makes them feel light:
- Thinner lenses: Higher index lenses (1.67 or 1.74) are thinner and lighter—game - changer for strong prescriptions.
- Smaller lenses: Rimless/semi - rimless frames reduce lens size, cutting weight.
- Under 15 grams = unnoticeable: A 10g frame vs. 15g frame? You won’t feel the difference—focus on lenses instead.
- Prescriptions: Always get one from a licensed optometrist—optical stores sometimes skip detailed checks.
- Fit > Fashion > Price: Don’t buy cheap frames (they break fast!) or overpriced ones unless you love them. The best frame feels like it was made for you.
- Luxury Picks: For pure titanium, try Lindberg (custom - fit, super light) or Charmant (classic, durable).
Next time you pick up a pair of glasses, you’ll know exactly what those temple arm numbers mean—and how to find frames that fit and flatter. No more guessing—just confidence!
