what size sunglasses do i need
You can figure out what size sunglasses you need by checking a few key measurements and matching them to simple size ranges (small, medium, large) plus your face width and shape.
Quick Scoop
- Sunglasses size is mainly about lens width , bridge width, and temple (arm) length.
- For most adults, “small / medium / large” sizes follow predictable millimeter ranges you can use even when shopping online.
- A fast hack: measure your face width (temple to temple) and match it to a lens-width range in mm.
Step 1 – Understand the numbers on frames
Most sunglasses have three numbers printed inside the arm, like: 55–17–140.
- First number = lens width (mm)
- Second = bridge width (mm)
- Third = temple length (mm)
These three tell you how wide the front is, how it sits on your nose, and how far the arms reach behind your ears.
Step 2 – Match to size (small / medium / large)
A common size guide looks like this:
| Overall size | Lens width (mm) | Bridge width (mm) | Temple length (mm) |
|---|---|---|---|
| Small face | ≈ 49–54 | [1][5]≈ 14–18 | [1]≈ 130–135 | [5][1]
| Medium face | ≈ 55–58 | [5][1]≈ 16–20 | [1]≈ 135–140 | [5][1]
| Large face | ≈ 59–63 | [1][5]≈ 18–22 | [1]≈ 140–145+ | [5][1]
Step 3 – Measure your face in 1 minute
You can do this with a ruler or tape in front of a mirror.
- Face width (temple to temple)
- Hold the ruler horizontally across your face at eyebrow level and measure from one temple to the other.
- Classify your face width
- Narrow: less than ~129 mm → look for lenses up to ~50 mm.
* Average: 130–139 mm → lenses around 51–55 mm usually work.
* Wide: 140 mm+ → lenses 56 mm and above.
You don’t need perfection; most people are comfortable in a small range rather than one exact number.
Step 4 – Check how they should fit
Once you know your range, the right sunglasses should:
- Not extend way past your temples and not look pinched or too narrow.
- Sit lightly on your nose without sliding or pinching (bridge size too small = squeeze, too big = slipping).
- Have arms long enough to reach just behind your ears without digging in or popping off (temple length).
If you already own a pair that fits well, use its numbers as your baseline and stay within ±2–3 mm on lens width and ±2 mm on bridge width.
Step 5 – Factor in your face shape
Size is about physical fit; shape is about how they look on you.
- Oval face: Most styles work; medium lens widths that are as wide or slightly wider than your face look balanced.
- Round face: Go a bit wider with more angular frames to add definition.
- Square face: Slightly larger round or oval frames help soften strong angles.
- Heart / diamond: Frames that balance a broader forehead or highlight high cheekbones (like cat-eye or rimless) work well.
You can treat these as style tips, not strict rules—comfort and confidence win.
Fast “What Size Do I Need?” shortcuts
If you want ultra-quick guidance:
- Narrow / small head → try lens width around 49–52 mm, small–medium bridge, 130–135 mm temples.
- Average head → start at 53–56 mm lenses, mid bridge (16–20 mm), 135–140 mm temples.
- Bigger head → 57–60+ mm lenses and 140 mm+ temples so the frame doesn’t pinch.
If you tell me your face width in mm (or send the numbers from a pair you own), I can suggest an exact size range for your next sunglasses.
Information gathered from public forums or data available on the internet and portrayed here.