E-commerce
June 26, 2026
Size selection is one of the leading causes of returns in fashion e-commerce. Customers hesitate between two sizes, compare with a brand they know, or do not know how to interpret a measurement guide.
The chatbot must make the size guide more useful. It explains how to measure, takes into account the cut, the material, the desired fit, and customer reviews, and then warns of limitations when the recommendation remains uncertain.
This guide shows how to use an AI chatbot to reduce size-related returns without giving an overly confident answer.
Summary
Why is the size guide alone not enough?
A size chart does not always tell how a garment actually drapes. An oversize fit, stretchy material, or personal preference can change the choice.
The chatbot should help the customer translate the numbers into a decision. It does not replace the guide: it makes it understandable.
The right size depends on measurements, but also on the cut, the material, and the desired comfort.
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What information should be requested?
The bot can ask for useful measurements, the usual size, the reference brand, the desired cut, the size worn by the model, the material, and the preference between fitted or comfortable.
It must ask only what actually helps. A customer who hesitates between M and L does not need a complete questionnaire if two measurements are sufficient.
How to explain the measurements?
The chatbot can indicate where to measure: chest, waist, hips, inseam, foot length or hand circumference depending on the product. It must explain that measurements should be taken without pulling too tight.
It can also distinguish between body measurements and garment measurements, as this confusion leads to many wrong choices.
How do you integrate fit and material?
A stretchy material can tolerate more variation, while a rigid material requires a more precise size. A slim fit may require sizing up if the customer wants more comfort.
The bot must link these elements to the exact product, not give a general rule applicable to all fashion.
How to manage uncertainty?
If the customer is between two sizes, the chatbot can explain the trade-off: tighter, more comfortable, longer, looser, or easier to alter. It must also remind them of the exchange conditions.
The tone must remain cautious. A size recommendation is never a perfect guarantee of fit.
Which flow to follow?
The flow should guide without adding complexity.
Identify the product, hesitated size, cut, material, and associated guide.
Collect the truly necessary measurements and comfort preference.
Compare measurements with the guide and product information.
Explain the recommended size, trade-off, and exchange conditions.
Transfer atypical sizes, inconsistent measurements, non-exchangeable products, and expert requests.
Which messages should be used?
To measure: "Compare your chest measurement to the guide, without pulling the tape measure tight."
If in doubt: "If you are between two sizes and prefer comfort, the larger size seems wiser."
To limit size service: "This recommendation helps flag the right size, but trying it on remains the only way to perfectly confirm the fit."
When to transfer?
The transfer is necessary if the product is not exchangeable, if the measurements are contradictory, if the customer needs expert morphological advice, or if a large order depends on the size.
The bot must transmit the product, guide, measurements, usual size, preference, recommended size, and any remaining doubt.
Which KPIs should be monitored?
Follow the size recommendations, returns due to size, exchanges, frequent hesitations, recommended then returned sizes, and questions about fits.
This data shows whether the size guide and fit descriptions need to be improved.
Which mistakes should be avoided?
Avoid recommending without moderation, ignoring the cut, guaranteeing a perfect fit, or hiding that a product is difficult to exchange.
The chatbot must reduce the risk of return, not eliminate all nuance.
How can Qstomy help?
Qstomy can connect the chatbot to the catalog, variants, size guides, stock levels, SMS campaigns, social content, and support rules to answer clearly, then hand over sensitive cases with an actionable summary.
The chatbot helps the customer move forward without inventing a reference, size, availability, or promotion that has yet to be confirmed by a reliable source.
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Key takeaways
Key Takeaways
A size guide becomes useful when it takes into account measurements, fit, material, and desired comfort.
What the customer must understand
The customer must understand why a size is recommended and what trade-off it involves.
The right limit for the chatbot
The chatbot can reduce returns, but it must transfer inconsistent measurements, non-exchangeable products, and expert requests.
Enzo
June 26, 2026
