SIZING & FIT

One size fits most kids.

One flexible sport fit, built to stay put through recess, the backseat, and bedtime. Roughly ages 5–12.

We didn't want parents guessing between half-sizes, so we built one well-chosen size. We measured commercial kids' frames with calipers and checked our frame against published size charts from Jan & Jul, Warby Parker and Pit Viper. Ours lands just above every kids' reference and just below adult narrow — deliberately slightly larger, never massive. Paired with a flexible frame, grippy temples and the included retainer strap, that covers most kids roughly 5 to 12.

The measurements

Frame width	130 mm
Hinge-to-hinge	120 mm
Lens width	47 mm
Bridge	17 mm
Temple length	130 mm (Aviator) / 112 mm (Shield)
Overall height	42 mm (Aviator) / 48 mm (Shield)

Written the standard way, that's 47-17-130 for the Aviator and 47-17-112 for the Shield.

One thing worth catching: the two frames share the same width and lens, but the Shield's arms are 18 mm shorter (112 mm vs. 130 mm). That's on purpose — the wraparound shape hugs the head and carries more of the fit, so it needs less arm. When you're comparing numbers, use the row for the frame you're actually picking.

Where we sit vs. the market

Every number below is from the brand's own published size chart or our caliper measurements.

Frame	Frame width	Lens width	Marketed for
Warby Parker Junior	120 mm	43 mm	kids optical
Jan & Jul M	125 mm	43 mm	2–6 yrs
Pit Viper Exec Junior	126 mm	—	junior
Night Game	130 mm	47 mm	most kids ~5–12
Adult narrow	135+ mm	48–50 mm	adult

Check against a pair they already own

This is the fastest way to know. Grab any pair of glasses or sunglasses your kid already wears and look on the inside of the temple arm — most kids' frames print three numbers there, like 47-17-130. That's lens width, bridge, and temple length, in millimetres. Compare those three to ours. If their current pair is within a few millimetres, you're in good shape.

The first two numbers (47 and 17) are the same on both our frames. Only the third — temple length — changes: 130 mm on the Aviator, 112 mm on the Shield. If their current pair has long arms, the Aviator is the closer match.

The retainer strap does real work

Every pair ships with an adjustable retainer strap, and it isn't an afterthought — it's what makes one size work at the younger end. On a smaller face it takes the slack out and keeps the frame put through a bedtime that involves more somersaults than it should.

Sizing questions

What size are these?

One size. 130 mm frame width, or 47-17-130 in standard eyewear numbers (the Shield runs 47-17-112 — same width, shorter arms). It fits most kids, roughly ages 5–12.

Will these fit my 4-year-old?

Likely yes — but they're on the larger side for a 4-year-old, so we'd rather be straight with you than oversell it. The included retainer strap helps a lot at that age. And returns are free, so trying them costs you nothing.

Will these fit my 11- or 12-year-old?

Usually yes. At 130 mm we're close to an adult narrow frame, so older kids tend to be well covered.

How do I check before buying?

Compare against a pair they already own. The three numbers are printed inside the temple arm — lens width, bridge, temple length. Ours are 47-17-130 (Aviator) and 47-17-112 (Shield).

Why only one size?

Because kids' head width changes less than people expect between 5 and 12. One well-chosen size, a flexible frame and a retainer strap cover most of that range — which means one less decision for you at checkout, and free returns if we called it wrong.