“Fashion brands invest millions in customer acquisition every year. Yet one of the biggest reasons customers don’t convert – or never come back – has nothing to do with marketing. “
If you want to reduce costly ecommerce returns, stay until the end – because the reason behind most returns might surprise you.
Hi, my name is Vesselena.
After more than 15 years in fashion design, pattern making, and running my own fashion brand, I kept seeing the same issue again and again.
Customers weren’t returning products because they disliked them.
They were returning them because they couldn’t find the right size.
I used to have my own fashion brand for 8 years.
When we started selling internationally – from the US to Japan – our return rates increased dramatically, reaching 30%. This was killing us.
We started thinking about what we could do.
The first thing we did was ask our customers for their body measurements, and we discovered that our general size chart was wrong.
The second thing I discovered, through thousands of customer interactions, was that finding the perfect size depends on three key factors:
✔ Garment design
✔ Fabric elasticity
✔ Personal fit preferences
Yet none of the existing size recommendation solutions considered all three when trying to recommend the right size to my ecommerce customers.
That made me think:
If the industry still cannot provide accurate size recommendations, then it’s time to build a better solution.
Especially for fashion brands where fit is everything and where there is simply no money to burn on unnecessary returns.
Vesselena and Alex – founders of SizeSense.ai
That though became the beginning of SizeSense.ai. – the most accurate size recommender.
The Truth Most Fashion Brands Don’t Realize
Most brands think they have:
✅ A traffic problem
✅ A conversion problem
✅ A customer acquisition problem
But much of the problem starts much earlier.
It starts the moment a customer asks:
“What if this doesn’t fit me?” That single moment of hesitation costs fashion brands billions every year.
And if customers don’t trust your size recommendation or you don’t give them any size recommendation, you face two outcomes: you lose the sale, or they order multiple sizes just to find the right fit – increasing your returns.
But First Let’s See Why Customers Still Can’t Find the Right Size
1. Bodies Don’t Fit One Shape
Most size charts are built around an hourglass body shape.
But only a small percentage of women actually have one.
The rest exist somewhere between sizes.
2. Fit Preferences Are Invisible
Some customers prefer a tailored fit.
Others prefer relaxed or oversized clothing.
A size recommendation without understanding fit preferences is incomplete.
3. Fabric Elasticity Is Missing
A size M in rigid denim and a size M in a stretch dress are completely different garments.
Yet most sizing tools treat them exactly the same.
4. Ease Is Never Explained
Customers don’t understand design ease, practical ease, or how garment measurements translate into real fit.
They simply know when something feels wrong.
5. Standard Sizing Doesn’t Exist
Every brand has its own sizing logic.
Every collection can fit differently.
Customers are expected to solve a highly complex sizing equation on their own.
So what you’re doing is making your customers guess.
And when customers have to guess, they don’t buy with confidence.
There is a hidden two-part system in the human brain that influences every purchasing decision.
The first part is the subconscious mind.
The subconscious is emotional. It is fast. It is responsible for feelings, intuition, habits, and instant decisions.
This is the part that says:
“I love this dress.”
“I can imagine myself wearing this.”
“This brand feels right.”
In fact, most buying decisions start here.
But then the second part of the brain steps in: the conscious mind.
The conscious mind is analytical. It looks for risks and tries to protect us from making mistakes.
It starts asking questions:
“Will this fit me?”
“What if it’s too tight?”
“What if I have to return it?”
“Am I wasting my money?”
And this is exactly where most fashion brands lose customers.
Because when you don’t provide enough sizing confidence, you force customers to stop relying on emotion and start thinking.
And thinking creates doubt.
Doubt creates friction.
Friction kills conversions.
Instead of imagining how beautiful they will look in your clothes, customers start calculating risks.
And once the conscious mind takes over, one of three things happens:
- They leave your website without buying.
- They order multiple sizes just in case.
- They buy, but with low confidence, making returns much more likely.
The goal is not simply to recommend a size.
The goal is to remove uncertainty before the conscious mind starts questioning the purchase.
Because when customers feel:
“This brand understands my body and I can trust this recommendation,”
their subconscious stays in control.
And people buy with confidence.
That is why fit is not just a sizing problem.
It is a trust problem.
The Hidden Cost of Size Uncertainty
When customers are unsure about sizing:
❌ They abandon their cart.
❌ They order multiple sizes.
❌ They make returns.
❌ They lose trust.
❌ They buy from competitors.
And every one of these actions directly impacts profitability.
Why Most Existing Solutions Don’t Work
Brands try to solve sizing with:
❌ Generic size charts
❌ Model measurements
❌ Customer reviews
❌ Height & weight calculators
❌ Virtual try-ons disconnected from sizing intelligence
But all these solutions share one fundamental problem:
They don’t truly understand fit.
Because fit is far more complex than a simple size chart.
Customers often find that their body measurements fall across two or even three different sizes, leaving them unsure which one to choose.
Most customers don’t realize that there is no universal sizing standard – every brand has its own sizing system, and even products within the same brand can fit differently.
Customers also don’t know about concepts such as ease. There is a significant difference between design ease (the extra room intentionally added for style) and functional ease (the space needed for comfort and movement).
On top of that, the required ease varies depending on the garment’s construction, fabric composition, and elasticity.
As a result, customers are expected to solve a highly complex sizing equation on their own – without having the knowledge of a fashion designer or pattern maker.
Two women can have identical heights and weights and still require different sizes.
Because fit is far more complex than simple body measurements.
The Real Reason Behind Returns
Sizing isn’t about numbers.
Fit depends on:
✔ Body proportions
✔ Body shape
✔ Fabric elasticity
✔ Garment construction
✔ Personal preferences
Most recommendation engines rely on incomplete data.
They don’t use real garment measurements.
They don’t understand fabric behavior.
They don’t understand fashion.
Imagine buying a table.
You know the dimensions of your room and the dimensions of the table.
Why should buying clothing be any different?
Customers should know whether a garment will fit before purchasing it.
Just by giving our customers accurate size recommendations we managed to decrease returns with 66%.
The New Era of Fit Intelligence SizeSense.ai – why we are different
At SizeSense.ai, we have an unique mechanism of calculating size.
SizeSense.ai is a size recommendation engine that combines:
✔ Customer body measurements
✔ Garment measurements
✔ Fabric elasticity
✔ Garment design
✔ Personal fit preferences
We also developed Fit System Builder (Beta version available) – as part of our size recommendation engine which turns fit from a subjective process into a data-driven system. Build consistent sizing frameworks in days, not seasons – reduce size inconsistency and make confident product decisions based on real fit data, not guesswork.
We did this to provide one thing:
A dress from our former fashion brand, ATTITUDE157
Confidence and RIGHT SIZE every time.
The same methodology that reduced returns in our own fashion brand by 66% is now embedded into SizeSense.ai.
Because Customers Don’t Buy Clothes.
They buy the feeling that:
“This will fit me and look good on me.”
And when that confidence is missing…
marketing budgets start leaking.
Fashion Brands Are Losing Millions Every Day
Brands invest millions into:
✅ Meta Ads
✅ Google Ads
✅ Influencer Marketing
✅ Email Campaigns
✅ Customer Acquisition
And then lose:
❌ Conversions
❌ Customers
❌ Loyalty
❌ Margins
❌ Lifetime Value
Simply because customers are not confident about sizing.
Why Selling Fashion Online Is So Hard
Because you’re not just selling a product.
You’re selling fit.
Something a living, moving body has to experience to believe.
And yet brands still expect customers to calculate:
- How fabric behaves
- How much ease is built into the garment
- Whether the garment runs small or large
- Which size aligns with their body shape
This is simply too much to ask.
And When Fit Becomes Clear, Everything Changes
✔ +250% Average Order Value
✔ +25% Conversion Rate Uplift
✔ -66% Returns
✔ +23% Customer Retention
All by solving one problem:
Giving customers confidence.
Our Vision
We believe the future of fashion isn’t more personalization.
It is:
Personalization Through Fit.
SizeSense.ai helps fashion brands turn fit into a competitive advantage by delivering accurate size recommendations that reduce returns, improve customer confidence, and increase conversions.
A future where every customer knows:
✔ What size to buy
✔ How a garment will fit
✔ And can shop with complete confidence.
Because the Biggest Problem in Fashion E-commerce Isn’t Traffic.
It’s uncertainty.
And every second a customer hesitates…
a brand loses money.
Imagine a World Where Customers Never Ask:
“Should I order S or M?”
Imagine a world where brands no longer spend millions acquiring customers…
only to lose them because of sizing issues.
That is the future we are building at SizeSense.ai. 🚀
Want to Reduce Returns and Increase Conversions?
Discover how Fit Intelligence can help your brand turn uncertainty into confidence.
Because brands spend millions on ads… and then lose customers because of sizing issues.
Right now, somewhere, a competitor of yours is fixing their fit problem.
Not with guesswork.
Not with a bigger size chart.
With actual fit intelligence engine like SizeSense.ai – fabric behavior, ease policy, construction logic, all built into how they recommend sizes.
The brands that solve this now aren’t just cutting returns. They’re taking your customers while you’re still debugging your size chart.
Fit intelligence and accurate sizing aren’t a nice-to-have anymore. They are the new customer acquisition channel – except it’s stealing acquisition from you.
Meet the founders
Vessie has extensive expertise in fashion design, apparel technology and ecommerce. She studied fashion design and technology in Kent State University in Ohio, US and also Escuela de Artes y Deseno, Burgos, Spain. She is the owner of the Attitude 157 fashion brand and the ideologist behind SizeSense.
Alex is one of SizeSense’s cofounders. A mechanical engineer fascinated by intelligent systems with a Ph.D. in Machine Learning for industrial applications, and an eMBA degree. Alex has a lot of entrepreneurial experience, and a deep knowledge in product design, systems modelling and prototyping, but also marketing and finance.
Bag by ATTITUDE157
Vesselena at the studio
Fashion Brands About Us
