"I'm usually a medium, but in this brand I'm a large, and in that one I'm somehow a small." If you've ever had a customer say something like this — or typed it yourself — welcome to the most common frustration in online fashion. A huge share of shoppers live between sizes, and for them, every purchase is a coin flip.
This isn't a niche problem. Ask any boutique owner and they'll tell you: the "I'm between sizes, what do I do?" message is one of the most frequent customer service questions they get. And every unanswered one is a sale that quietly dies at checkout.
Why nobody's size means the same thing twice
There is no law that says what a "medium" is. Every brand sets its own measurements, and many adjust them deliberately — some brands cut generously so customers feel good about fitting a smaller size, others cut slim for a fashion-forward fit. Add different fabrics (a stretch crepe forgives; a structured satin doesn't), different designers within one label, and seasonal tweaks, and you get the current chaos: a woman can be three different sizes in three different stores, sometimes in three dresses from the same store.
So when your customer says she's "between sizes," she's describing reality accurately. The sizes themselves are the moving target, not her body.
What your between-sizes shoppers are actually asking
Strip away the wording and every between-sizes question is really one question: "If I order this, will I be sending it back?" She's not confused about the concept of sizes — she's trying to avoid the hassle, the return shipping, and the disappointment of a dress that doesn't fit.
That means your job isn't to educate her about size charts. It's to remove the risk from the decision. Everything below does that.
What you can do as a boutique owner
1. Publish the garment's real measurements — not the chart's
Size charts describe an idealized body. Garment measurements describe the actual dress in your hands: armpit to armpit, waist, hips, total length, measured from the sample. A between-sizes shopper who knows her own bust measurement can compare it directly and decide in seconds. This single addition converts more hesitant shoppers than any other line of text on a product page.
2. Tell her which way to go, product by product
"Between sizes? Size up — the bodice runs snug." That one sentence is worth more than a paragraph of fabric composition. You know how each dress fits because you've held it, steamed it, maybe tried it on a fit model. Put that knowledge on the page. Generic advice ("when in doubt, size up") is useless; specific advice per product is gold.
3. Show the dress on more than one body
If every dress is photographed on the same sample-size model, your between-sizes shopper has nothing to compare herself to. You don't need a full diverse model roster for every product — even showing the dress on two different sizes, or adding each model's height and worn size to the photo captions, gives her the reference points she needs.
4. Answer the question before she has to ask it
Add a short "Fit notes" block to every product page, right near the size selector. Three lines: how it fits (true to size / runs small / runs generous), what to do between sizes, and anything structural (smocked back, stretch lining, no stretch). Shoppers read what's next to the button they're about to click — they don't go hunting in tabs.
5. Let her try it on herself
The ultimate answer to "I'm between sizes" is seeing the dress on her own body. Virtual try-on puts a "Try It On" button on your product pages — she uploads a photo once, and in seconds she sees your dress on herself instead of a model. Size up or size down stops being a guess because she can see the fit. For the between-sizes shopper, this is the closest thing to a fitting room the internet has.
A note on "just size up"
You'll see this advice everywhere: "between sizes? Always size up, tailoring is cheap." It's not terrible advice, but it puts the work — and the cost — on your customer. A boutique that helps her get it right the first time earns something a tailor can't give you: the next order, placed without hesitation.
The bottom line
Between-sizes shoppers aren't difficult customers. They're careful customers — and careful customers become loyal ones once a store proves it won't waste their time. Real measurements, honest per-product fit notes, and a way to see the dress on themselves: do those three things and the "what size should I get?" messages turn into orders.
Frequently asked questions
Should I size up or size down when I am between sizes?
It depends on the fabric and the cut, which is exactly why generic advice fails. As a rule of thumb: size up in structured, non-stretch fabrics (satin, taffeta, denim) where a too-small garment can't be saved, and consider sizing down in very stretchy knits that grow as you wear them. But the real answer is always product-specific — check the boutique's fit notes for that exact dress, because the same shopper should size up in one dress and down in another.
Why do I wear a different size in every brand?
Because there is no standard. Every brand defines its own size measurements, and many deliberately adjust them — some cut generously, some cut slim. Different fabrics, different designers within the same label, and seasonal changes all shift things further. Your body didn't change between stores; the ruler did.
Do customers actually use size charts?
Far fewer than boutique owners assume. In merchant discussions, owners routinely report that only a small fraction of shoppers ever open the size chart — most buy based on the size they usually wear, the photos, and gut feeling. Charts fail because they describe an abstract body in numbers, while the shopper is asking a concrete question: "will this fit me?" Anything that answers that question directly — fit notes, real measurements, try-on — outperforms the chart.
Does the same size fit differently even within one brand?
Yes, constantly. Different fabrics behave differently — a stretch crepe and a structured satin in the same labeled size will fit like different sizes. Different designers and product lines within one brand often use different fit blocks, and seasonal tweaks happen quietly. This is why "I always wear a medium in this brand" still produces surprises.
I am tall, so should I just buy the bigger size to get the length?
Usually not — sizing up for length gives you extra width everywhere else, and a dress that's too wide in the shoulders or bust looks worse than one that's slightly short. Better options: check the garment's actual length measurement against a dress you own that fits, look for tall-specific lines, or budget for a hem adjustment. Length and width are different problems and need different solutions.
How can I find my right size when shopping online without ordering two sizes?
Combine three things: your own key measurements (bust, waist, hips — measured once with a tape), the garment's real measured dimensions from the product page (not the generic size chart), and the boutique's fit notes for that specific piece. And where it's available, use virtual try-on to see the garment on your own photo — it answers the question your measurements can't: how it actually looks on you. (If bracketing is your bigger headache, read our guide on how to stop customers ordering two sizes and returning one.)
RealityTry lets your between-sizes shoppers see your dresses on themselves before they order — add the Try It On button to your product pages, no code needed.