
Sizing chart
Kids' ski helmet size chart, by the one measurement that works
Head circumference to helmet size, with the published youth ranges from three brands side by side and the five-second fit check.
Helmet, ski and boot size charts you can measure a child against at the kitchen table, and honest arithmetic on what is worth buying for someone who will outgrow it.
Nothing here has been tested by us. How we pick · Who writes this · How we earn

In this section
Sizing charts and cost arithmetic are free to read and always will be. The ranked picks carry affiliate links.

Sizing chart
Head circumference to helmet size, with the published youth ranges from three brands side by side and the five-second fit check.

Sizing chart
Height-to-length bands with the arithmetic shown, the weight adjustment, and the published lengths brands actually sell.

Sizing chart
Mondopoint to US kids shoe size, the paper-and-wall measuring method, and the growth allowance that is much smaller than you think.

Guide
Cold hands, wrong boots and no plan for lunch. What actually ends a family ski day, and how to prevent each one.

Best kids' helmet
Three certified youth helmets from $39.99 to $110, with the size ranges side by side and the growth allowance spelled out.
Top pick: Retrospec Comstock Kids

Best kids' goggle
Four youth goggles from $29.99 to $40, two of them over-the-glasses, ranked on published UV and anti-fog construction.
Top pick: OutdoorMaster Falcon Kids

Best kids' jacket
Three youth jackets from $55 to $155, with the cost per day on snow and the second-child effect spelled out.
Top pick: Arctix Kids Jackalope Insulated Jacket
No live price is currently verified, so every button here reads Check price rather than a number we cannot stand behind. Why we do it that way.
Sizing a child for snow is the problem families actually have, and it is the one the industry answers worst. Search for a children’s helmet size and you get a table of ages, which is useless: two seven-year-olds can be four centimeters apart in head circumference, and four centimeters is a whole size.
So every chart on this site is built on a measurement you take yourself, at home, with a tape measure or a pencil and a wall. Age appears only as context. The three charts are helmet size by head circumference, ski length by height and weight, and boot size by foot length in millimeters.
The honest answer differs by item, and lumping them together is where most advice goes wrong:
This is the arithmetic families come here for, and we run it on the buy versus rent page in full. The short version, computed on our published convention of two seasons at five days each:
Every cost-per-day figure on this site is computed for one wearer. If a jacket goes on to a younger sibling, halve it. If it goes to two, divide by three. This is the single biggest lever in family ski gear economics and nobody publishes it, because it is the calculation that most often says do not buy the expensive one.
A child who is cold, or in a boot that does not fit, will not enjoy a lesson no matter how good the instructor is. Almost every reported case of a child hating skiing traces back to hands, feet or a badly fitted boot. Getting those three right is worth more than every other decision on this page combined, which is why gloves and boot sizing get their own pages.
Deliberately, not on this page. A children’s helmet roundup lives in the helmets section, children’s goggles in goggles, children’s jackets in outerwear. Keeping each category’s picks on one path means a single page carries the depth rather than two near-duplicates competing with each other. They are all tiled above.
Measure the head about a centimeter above the eyebrows and around the widest part at the back, then match that measurement to the maker’s own chart. Age is not a reliable guide. The measurement steps and a brand-by-brand table are on the kids helmet size chart.
No. A helmet that moves when the head shakes is too big and does not do its job. Buy the size that fits now, and prefer a helmet with a published dial adjustment range, which covers growth without ever being loose.
For skis and boots, renting or a seasonal lease almost always wins for a growing child. For a helmet, goggles, socks and gloves, buying wins on any realistic number of days. The full arithmetic is on buy versus rent.
Most resort ski schools start group lessons around age three to four, and many run shorter private sessions younger. We do not have a view worth publishing on readiness, but we do have one on gear: the equipment has to fit properly at any age, and a badly fitted boot is the most common reason a small child asks to stop.