The R$7.5 Billion Problem: Returns in Brazilian Fashion E-commerce
In Brazil, it is estimated that fashion e-commerce loses around R$ 7.5 billion per year due to returns and exchanges. And the number one reason? Size issues. “It was too big,” “it was too tight,” “the length wasn’t what I expected”—these are the most common reasons cited on exchange forms, accounting for up to 52% of all returns in the fashion sector.
The most straightforward—and surprisingly underutilized—solution is the size chart. A simple tool that requires neither sophisticated technology nor significant investment, and which can reduce returns due to sizing issues by 20 to 35% when properly implemented.
At WX3, where we manage over 45 fashion e-commerce sites, the size chart is treated as a strategic component, not a secondary detail. Stores in our ecosystem that have invested in professional size charts have seen a direct impact on their return rate—and, consequently, on their profit margin.
Why most stores’ size charts are useless
The problem isn’t the absence of a size chart—most e-commerce sites have one. The problem is that it’s generic, confusing, incomplete, or hidden. The most common mistakes:
Mistake 1: A generic size chart for the entire catalog
A single “standard” chart for all products. The problem? A loose dress and a pair of skinny jeans have completely different cuts. A size M oversized T-shirt may have shoulder measurements that correspond to a size L on a fitted blouse. Each cut needs its own chart—or, at the very least, each product category.
Mistake 2: Measurements the customer doesn’t understand
Size charts that show "bust: 96cm, waist: 78cm, hips: 104cm" without explaining where each measurement is taken. The average customer (who makes up the majority) doesn’t know if "bust" refers to the chest circumference, the width of the garment when laid flat, or the circumference with ease. Result: they guess the size, and the likelihood of error skyrockets.
Mistake 3: Hidden or hard-to-access size chart
The chart exists, but it’s in a tiny link below the description that the customer has to search for. If the customer needs more than two clicks to find the size chart, it might as well not exist. The chart should be visible and directly accessible on the product page, next to the size selector.
Mistake 4: Lack of instructions on how to measure
Even if the chart is there, without a visual guide showing how the customer should measure themselves (with a measuring tape, in what position, wearing what clothes), the measurements they provide will likely be incorrect. And incorrect measurements + correct chart = wrong size anyway.
Anatomy of a measurement chart that works
An effective size chart has six components:
1. Product measurements, not body measurements
There are two approaches: body measurements (“this garment is recommended for those with a waist between 74–78 cm”) and garment measurements (“the garment’s waist measures 80 cm”). The most effective approach is to offer both, but prioritize the measurements of the garment itself—this is what the customer can verify with a measuring tape at home, by comparing it to a similar garment they already own.
2. Illustration or photo showing where to take each measurement
A simple diagram showing exactly where each measurement is taken. For a blouse: shoulder width, length, bust, waist, sleeve length. Each measurement with an arrow indicating the exact point. Images work much better than text for this.
3. Responsive and accessible table
Remember: 78% of traffic comes from mobile devices. The table needs to be readable on a 5.5-inch screen without zooming or horizontal scrolling. Formats that work well on mobile:
- Table with horizontal scrolling (but with a visual cue that there are more columns)
- Dropdown by size (select M to see only the M sizes)
- Stacked cards (one card per size with all measurements)
4. Contextual size recommendations
In addition to the static table, include contextual guidance: "This style runs large—if you’re between sizes, we recommend the smaller one" or "Fitted cut—if you prefer comfort, go up a size." This guidance significantly reduces indecision and errors.
5. Size conversion
If your brand sells internationally (or if customers are accustomed to American or European sizing), include a conversion chart: P = S = 36, M = M = 38, G = L = 40. This is especially important for footwear, where confusion between sizes is rampant.
6. Integrated social feedback
Allow customers who have already purchased an item to indicate whether it fit “smaller than expected,” “as expected,” or “larger than expected.” This collective feedback is invaluable: when 73% of buyers say the dress fits “smaller than expected,” the next customer knows to go up a size. Major e-commerce sites like ASOS and Zara already use this feature successfully.
How to create size charts for each category
Blouses and T-shirts
Essential measurements: total length, bust (circumference or flat width), waist, shoulder-to-shoulder, sleeve length. For cropped tops, add “front length” measured from the neckline to the hem.
Pants and shorts
Essential measurements: waist, hips, inseam (crotch), total length, hem width. For jeans, specify whether the measurements are before or after the first wash (jeans without spandex can shrink up to 5%).
Dresses
Essential measurements: total length (measured from the shoulder to the hem), bust, waist, hips, sleeve length (if applicable). For dresses with elastic or a tie at the waist, indicate the minimum and maximum measurements.
Shoes
Essential measurements: insole length (in cm), width. Include a BR/US/EU conversion chart. Crucial tip: ask the customer to measure their foot with a sheet of paper and a ruler—it’s more accurate than using their usual shoe size, since every brand has its own shape.
Lingerie and Underwear
Category with the highest rate of size exchanges. Essential measurements: bust (underbust + measurement at the fullest point to calculate cup size), waist, hips. Include a detailed guide on how to measure correctly—measurement errors of 2–3 cm in lingerie completely change the size.
Technical implementation: where the size chart should be placed
On the product page
The chart should be accessible with a maximum of 1 click from the size selector. Formats that work:
- Modal/popup: A “Size Guide” link next to the selector opens an overlay with the chart. Advantage: doesn’t clutter the page. Disadvantage: one extra click.
- Accordion: Expandable section below the description. Advantage: everything on the same page. Disadvantage: may fall below the fold.
- Tab: Dedicated tab on the product page (Description | Size Chart | Reviews). Advantage: organized. Disadvantage: content hidden by default.
One of the strategies we implement for our clients at WX3 is to place the size chart link immediately below the size selector, with visual emphasis (ruler icon + text "What’s my size?"). This ensures the customer sees the option exactly when they need it.
Schema markup for size chart
Use structured data (schema.org/Product with size properties) so that Google understands the available sizes. This can improve rich snippets in search results and facilitate filtering on Google Shopping.
The impact on the numbers: before and after
Aggregated data from stores in the WX3 ecosystem that implemented professional size charts:
- Size exchange rate: Average reduction of 28% (ranging from 18% to 35% depending on the category)
- Conversion rate on the product page: Average increase of 5.2% (more confident customers buy more)
- Return shipping costs: 22% reduction (fewer returns = less return shipping + processing)
- NPS (Net Promoter Score): Average increase of 8 points (more confident shopping experience)
- Average order value: 3.7% increase (confidence in sizing encourages customers to add more items to their cart)
DressOn: The evolution beyond the size chart
The size chart is essential—but it has an inherent limitation: it tells the customer the garment’s measurements, but doesn’t show how the garment will look on them. A pair of pants with the right measurements may still have a fit the customer doesn’t like (waist too high, legs too wide, length odd for their height).
This is where DressOn, WX3’s virtual fitting room, comes in. Using artificial intelligence, DressOn allows the customer to visualize how the garment would look on their body—or on an avatar configured with their exact measurements. It combines the objective information from the size chart with the visual experience of a physical fitting room.
The size chart answers the question, “Will this size fit me?” DressOn answers the more complex question: “Will this style look good on me?” Together, they tackle both sides of the sizing problem that leads to returns.
Stores in the WX3 ecosystem that combine a professional size chart with DressOn report return rates due to dissatisfaction with size/fit that are up to 40% lower than the market average. In a segment where each return costs between R$ 30–80 in reverse logistics (not counting the item that comes back and needs to be reprocessed), this figure directly impacts the business’s financial sustainability.
Practical checklist: implement in one week
Don’t wait for the perfect system to get started. Here’s an action plan to implement efficient sizing charts in 7 days:
Days 1–2: Map out all the different styles in your catalog. Group products that can share the same size chart (all basic T-shirts, all midi dresses, etc.).
Days 3–4: Take the actual measurements for each group. Use physical garments, a measuring tape, and a trained person. Record the following in a spreadsheet: size, bust, waist, hips, length, and sleeve length (as applicable).
Day 5: Create visual diagrams. This could be a photo of the garment with arrows indicating where each measurement is taken. Free tools like Canva work perfectly.
Day 6: Write the “how to measure yourself” guide. Keep the text simple and straightforward, with a photo or video of someone measuring themselves with a measuring tape.
Day 7: Implement it in the store. Link each size chart to the correct products. Place the link next to the size selector. Test it on mobile.
A size chart isn’t sexy. It won’t go viral on TikTok. But it’s one of those quiet improvements that directly impact your e-commerce’s bottom line—reducing costs you’re already paying and improving the experience you’re already delivering. If you haven’t implemented a professional size chart yet, start today. Your customers—and your bottom line—will thank you.