To find the right size glasses, match frame measurements and width to your face so the lenses sit centered and the frame feels snug, not tight.
Buying new frames feels much easier when you know how to pick frames in the right size instead of guessing. A frame that fits well keeps your vision clear, stays in place through the day, and feels comfortable on your nose and ears from morning until late night.
You do not need special tools. With a mirror, a ruler, and a pair that already fits reasonably well, you can read the sizing numbers, match them to your face, and narrow down frames online or in store with far more confidence at home today.
How To Find The Right Size Glasses Step By Step
This section walks through the sizing steps in a simple order you can follow at home. Work through each step once and you will know the size range that suits you at home first.
Read The Numbers On Your Current Glasses
Start with any pair you already own, even an old set. Turn the frame over and look along the inside of the temple arm. In most modern frames you will see a short row of numbers such as 52–18–140 printed or engraved near the hinge.
That short code holds the core sizing data. The first number is lens width in millimetres, the second number is bridge width, and the last number is temple length from hinge to the end that curves behind your ear. The same three measurements show up in almost every size chart.
| Measurement | Typical Range (mm) | What It Changes |
|---|---|---|
| Lens Width | 48–55 | How wide each lens is from side to side |
| Bridge Width | 16–22 | How the frame rests on the nose |
| Temple Length | 135–145 | How the arms reach behind the ears |
| Frame Width | 125–140 | How the whole frame lines up with your face |
| Lens Height | 30–40 | Room for progressive or bifocal lenses |
| Nose Pad Spread | Varies | Pressure points at the top of the nose |
| Temple Tip Curve | Varies | How firmly the arms hug behind the ear |
If you wear prescription lenses, stay close to the numbers that already work unless that pair clearly pinches or slides. Keeping lens width, bridge width, and temple length near your current set usually keeps vision and comfort in a safe range.
Measure Your Frame Width
Frame width decides whether your glasses feel balanced or awkward. Set the glasses on a flat surface and measure straight across the front from the far left edge of the frame to the far right edge. A ruler marked in millimetres gives you a clear reading.
Now stand in front of a mirror. Hold that same ruler from one temple to the other, just above your ears. That distance is the rough width of your face across the eyes. Your frame width should sit close to that number so the frame neither sticks out past your temples nor leaves wide gaps at the sides.
Match Frame Size To Your Eyes
A pair can match your face width yet still feel off if the lenses sit too far in or out from your pupils. When you try on frames, look straight ahead in a mirror. The centre of each lens should sit close to the centre of each pupil.
If the lenses feel narrow and your eyes sit near the inner corners, you need more lens width or a slightly wider bridge. If your eyes sit near the outer corners, the frame may be too wide for you. Keeping those two points in mind helps you judge fit in seconds.
Choosing Frame Sizes For Your Face Shape
Face shape and face width also affect which frame sizes and shapes flatter you. No strict rule fits everyone, yet a few short checks help you dodge frames that will never sit well on you.
Check Your Face Width Category
Stand in front of a mirror again and measure straight across from one temple to the other. Then compare that number to your ideal frame width. Many opticians group faces into three loose bands: small faces around 125 millimetres or less, medium faces around 130 to 135 millimetres, and larger faces around 136 millimetres and above.
If your frame width is much smaller than your face width, the frame will pinch or look cramped. If your frame width is much larger, the glasses can slip, feel loose at the sides, or appear out of proportion in photos. Matching those two numbers within a few millimetres brings you closer to a balanced fit.
Balance Frame Height And Cheek Line
Frame height matters too, especially if you wear progressives or bifocals. When frames sit too low on your cheeks, the bottom edge can dig in when you smile. When they sit too high, your eyebrows may hide behind the top rim.
Try frames while you smile, talk, and look down at your phone. The lower edge should hover just above your cheeks instead of pushing into them, and the top line should sit just below your eyebrows or gently follow their curve.
Use Trusted Guides When Shopping Online
If you buy frames on the web, do not skip the sizing sections. Many retailers link to independent resources or eye health organisations that explain glasses measurements step by step. One helpful starting point is the American Academy of Ophthalmology guide on choosing eyeglasses, which explains how frame design, lens type, and fit work together for clear vision and day long comfort.
Health information sites such as the MyVision.org guide on measuring eyeglasses also break down lens width, bridge width, temple length, and lens height, and show how those measurements tie back to the size of your face.
Fit Checks When You Try New Frames
Once you know your basic numbers, you still need to test how each frame feels in real life. Small differences in bridge shape, nose pads, and temple curve can turn a technically correct size into a frame that either slides or squeezes.
Bridge Fit And Nose Comfort
The bridge should spread weight evenly across the upper nose instead of digging into one narrow point. For plastic frames without adjustable pads, the bridge should sit flush against the nose without gaps. For metal frames with pads, the pads should rest flat against the skin without sharp edges or harsh pressure.
If your glasses slide down often, your bridge width may be too large, the pads may sit too low, or the frame may be too heavy for your nose. If you see red marks that last long after you take the frame off, the bridge or pads may be too narrow, even when the rest of the frame feels fine.
Lens Position And Field Of View
When you look straight ahead, your pupils should sit near the centre of each lens. If they sit far above, below, or toward one edge, the frame shape or size is off and you may notice blur or strain at the edges of your view.
Common Fit Problems And What To Change
Many people ask about the right size glasses only after running into comfort problems. Match each symptom to a likely sizing fix and adjust the numbers on your next pair.
| Fit Problem | Likely Size Issue | What To Adjust |
|---|---|---|
| Glasses slide down nose | Bridge too wide or frame too heavy | Choose narrower bridge or lighter frame |
| Pressure at sides of head | Frame width or temple length too small | Pick wider frame or longer temples |
| Red marks on nose pads | Bridge too narrow or pads poorly adjusted | Try wider bridge or have pads adjusted |
| Lenses sit below eye line | Bridge sits low or temples too long | Choose higher bridge or shorter temples |
| Frames touch cheeks when you smile | Lens height too tall or frame too large | Pick shorter lenses or smaller frame |
| Eyes near inner lens edge | Lens width too small or bridge too narrow | Choose wider lenses or wider bridge |
| Eyes near outer lens edge | Frame too wide for face | Pick narrower frame or smaller size range |
When To Get Help From An Eye Care Professional
Home measurements give you a solid starting point, yet an eye care professional can still add value. An optometrist or ophthalmologist can confirm your prescription, measure your pupillary distance, and adjust bridge fit, temple curve, and frame tilt so your everyday glasses feel stable and comfortable.
Quick Checklist For Your Next Pair
Use this quick checklist while you shop so each new frame starts from a size that already works for you.
- Write down lens width, bridge width, temple length, and frame width from a pair that fits well.
- Match frame width to your face width within a few millimetres so the frame lines up with your temples.
- Check that your pupils sit near the centre of each lens when you try frames on.
- Watch how the frame behaves while you talk and smile to be sure it does not dig into cheeks or slide down.
- Arrange a quick fitting tweak if anything pinches, slides, or feels off during the first week.
Once these points check out, you can choose more colour and style knowing the basic size already suits your face.