The Coordinator's Guide to Size Guides

If you run enough team stores, a pattern emerges: the coordinators who never hear anything about sizing and the ones who field a hundred angry texts are almost the same people running the same items. The difference is entirely in how sizing information is presented up front.

This guide is the cheat sheet for not being the second kind of coordinator.

The core problem

Athletic apparel sizing is not standardized. A women's medium at one brand fits like a women's small at another. Kids' size 10 can fit an actual 8-year-old or an actual 12-year-old depending on the manufacturer. A unisex small cut for a compression fit is a women's extra-small in lifestyle terms.

Parents don't know this. They know what size their kid wore last year, in a brand they already know. If your store's product pages don't translate between those two worlds, you will field exchange requests for the next three months.

The three pieces of information that matter

Every apparel product in your store should display three things, no exceptions:

1. Chest (or waist) measurement in inches, not just a letter. A medium with a 38-inch chest is unambiguous. A medium by itself is a guess.

2. A fit descriptor. "True to size," "runs small," "fitted cut," "relaxed fit." One short phrase that orients a human brain before they commit.

3. A reference garment. "If your athlete wears a 10 in Under Armour tees, order a youth medium here." Parents have an anchor point already — give them the math.

If you're running on a platform that only shows size letters, you can add all three of these yourself in the product description. It is worth the ten minutes per product.

Handling youth vs. adult sizing

The single biggest source of exchange requests is a parent ordering an "adult small" for their 11-year-old based on an anchor garment that was actually a youth large. Ideally your store separates youth and adult cuts into different products so they can't be confused. If that isn't possible, write the crossover explicitly on the page: "Adult XS roughly equivalent to Youth L."

Teams with kids in the 9–13 age range should assume that a third of orders sit in the overlap zone. Plan for it.

Don't ask families to "order up a size" for growth

Two counterintuitive things are true simultaneously:

1. Kids grow.
2. Ordering up a size because kids grow causes more exchange requests than ordering true to size.

The reason: "order up" advice creates a year-long garment that fits poorly for the first six months, and by the time it fits correctly, the season is over and nobody wears it again. Parents see this and feel like they wasted money. The better framing is "order for right now, plan for a refresh next season." Season-over-season reorders are what turn a team store from a one-time event into a revenue loop.

Compression, performance, and suit sizing

These need their own conversation. Unlike t-shirts and hoodies — where "close enough" fits fine — a racing suit, compression base layer, or bike short has a tight tolerance window. A women's open-back racing suit that's half a size too large will literally not stay on during a race.

For compression and performance products specifically:

• Bold the "runs small" language if the cut is intentionally tight.
• Link a fit video if the manufacturer has one. Watching someone put on a racing suit explains more than any size chart.
• Offer a try-on window before the store closes for teams that have a facility available. Even a 30-minute session solves most of the anxiety.

The size profile pattern

A technique that works well for teams with an established roster: collect sizes from families once, store them on the athlete's record, and have the checkout pre-populate suggested sizes automatically. Parents don't have to measure their kid every time you open a store — the system remembers.

This turns the uncertainty-driven exchange problem into an infrequent "they grew, update the profile" problem, which is much smaller. If your platform supports size profiles, use them aggressively.

A note on exchanges

No matter what you do, you will get some exchanges. Aim for under 5% of orders — that's achievable with decent size information. Above 10%, something is wrong with how your store is describing sizes.

Most on-demand apparel platforms don't do free re-production for size errors because each garment is made to order. Be clear about the exchange policy up front on the checkout page. Families who understand the policy before ordering rarely complain about it after.

The one-line rule

If you remember one thing from this guide: every product page must tell a parent, in their language, which size fits their kid's known reference garment. If a parent has to guess, they'll guess wrong, and you'll be the person fielding the follow-up.