How Should I Measure IPD, Head Width, and Nose-Bridge Fit Before Buying Display Glasses?

IPD decides which display glasses and which size to buy, the nose bridge decides whether the whole picture sits in view, and head width decides how comfortable the glasses stay through a long film or a flight. All three can be worked out at home with a smartphone, a mirror and a pair of glasses that already fits well.

Each measurement maps to something specific on RayNeo display glasses. IPD selects the S, M or L size of RayNeo GT Max. Nose-bridge shape tells you which of the included nose pads to start with. Head width points to the frame style that suits you, from the one-piece GT series to the flexible temples of RayNeo Air 4 Pro.

1. Measure your IPD

IPD, or interpupillary distance, is the distance between the centers of your pupils. In display glasses it decides whether each eye lines up with the center of its optical viewing area, which gives the clearest, most comfortable view. It is the one measurement chosen when ordering, so it comes first. Any one of three routes gives the number:

1. The RayNeo IPD tool. Open ipd.rayneo.com in your smartphone's browser and follow the on-screen steps.
2. Your eye prescription. Many prescriptions list PD, which is the same measurement. A single number such as 63 is your total. Two numbers such as 31.5 and 32 are per-eye values, and their sum is your total IPD. The distance PD, the value used for everyday distance glasses, is the one to use rather than a near or reading PD.
3. A mirror and a ruler. With glasses off, stand about 20cm from a mirror and hold a millimeter ruler flat against your brow. Close your right eye and line the zero mark up with the center of your left pupil, then close your left eye and read the mark at the center of your right pupil.

With a number in hand, the model choice follows. GT Max comes in three IPD sizes: S for under 64mm, M for 64 to 67mm, and L for over 67mm. RayNeo GT is built around a 64mm IPD, and adjusting its nose pads and wearing position centers the image. Air 4 Pro aligns the display through fit, with its nose pads and temple angle centering the full screen. Our guide to GT and GT Max IPD options compares the two GT models size by size.

2. Read your nose bridge

The nose bridge sets the height of the glasses on your face, and that height decides whether the top and bottom of the picture sit inside your view. Your current glasses are the best measuring tool here.

1. Put on a pair that fits and look into a mirror. Watch where the frame comes to rest after a minute of normal wear.
2. Note the resting point. Glasses that slide down your nose or rest on your cheeks point to a low or flat bridge. Glasses that sit high with a clear gap above the cheeks point to a higher bridge.
3. Look at the nose pads of that pair. Pads that are already raised on adjustable arms, or a frame with built-up pads, also point to a low bridge.

A low bridge calls for a taller nose pad, which lifts the optics to eye level. A high bridge calls for a lower pad. The nose pad's job is to center the display, so this reading sets the starting pad, and the setting that centers the picture becomes your everyday one.

Every pad comes in the box, so the bridge reading guides your first choice rather than your order. GT Max ships with three nose pads in S, M and L heights, GT with two, and Air 4 Pro with 3-position nose pads plus a nose pad component.

3. Gauge your head width

Head width is about pressure and stability over time. Glasses that are too tight press behind the ears and at the temples, while glasses on a narrower head tend to slide forward when you look down. The useful reading here is how frames behave on you, not a number.

1. Recall the sides. Frames that often feel tight at the temples or leave marks behind the ears point to a wider head.
2. Recall the slide. Frames that creep forward when you look down, or often need tightening, point to a narrower head.
3. Recall the adjustments. Frames that an optician usually bends to fit point to a head that suits adjustable temples.

These readings point to a frame style rather than a size. GT and GT Max are built as a sports-car-inspired unibody, with fit tuned at the nose pad and four anti-slip temple pads in the box to keep the arms steady. Air 4 Pro takes the adjustable route, with flexible temples and a 9-way flexible adjustment system, which suits heads that usually need a frame adjusted.

Weight matters as much as width for long sessions: GT weighs 68g, Air 4 Pro 76g and GT Max 78g. Our guide to glasses for comfortable long viewing looks at full episodes and films on GT and GT Max.

Size and fit chart

Air 4 Pro is not ordered by IPD size. Its nose pads and temple angle center the full screen in your field of view.

Put together, the three readings usually point to one pair. An IPD near 64mm with the lightest possible frame as the priority leads to GT. An IPD below 64mm or above 67mm, or a wish for the widest picture, leads to GT Max in the matching size, with its 59° field of view and 267 inch cinema display. A head that usually needs frames adjusted, or a first pair of AR glasses, leads to Air 4 Pro.

FAQ

My two eyes measure differently from the center of my nose. Which size fits?

Should I measure with my glasses on or off?

What if my IPD lands right between two GT Max sizes?

Once the readings are in hand, the order is simple: RayNeo GT Max in the size that matches your IPD for the biggest picture, RayNeo GT at 68g for IPDs around 64mm, or RayNeo Air 4 Pro for a flexible, adjustable fit.