Size recommendation
A size recommendation is guidance shown to a shopper, usually on the product page, about which size of a garment to order. It is generated by comparing what is known about the shopper — measurements, height and weight, fit preference, or past purchases — against the product’s size data, and it exists because clothing sizes are not standardised between brands or even between products.
How size recommendations are generated
Most tools ask the shopper a few questions — height, weight, age, preferred fit — and map the answers onto the product’s size chart. Others compare the garment against brands the shopper already owns, or estimate body measurements from a photo. Whatever the method, the output is only as reliable as the size chart underneath it: if the chart is wrong about how a size measures, or the garment runs small, the recommendation inherits the error.
Why your own size charts matter
Generic sizing databases assume your medium behaves like everyone else’s medium, which is exactly the assumption that causes wrong-size orders in the first place. Recommendations built on your own size charts reflect how your garments actually measure. Looksy’s Size Help works this way — it uses your product size charts rather than a third-party database. The practical consequence for merchants: keeping those charts accurate and complete is the highest-leverage sizing work you can do.
What a size recommendation cannot do
It cannot rescue a missing or inaccurate size chart, and it cannot settle taste: some shoppers want the oversized fit the model wears, others want it fitted, and no algorithm knows which without asking. Nor does it come with a guaranteed effect on returns — Looksy publishes no benchmark figure. If you want to know whether size guidance is working for your store, compare size-related return reasons for guided and unguided orders over a full season.
Sources: the public Shopify App Store listing for Looksy. Last checked 27 July 2026.
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