Everything you'd want to know before you install.
A detailed look at how DataFirefly Size Guide — PrestaShop 8 & 9 module works, why we built it the way we did, and the thinking behind the features above.
What does this module do?
On apparel and footwear stores, more than 20 percent of returns are caused by sizing issues. The fix: show a clear, contextual size guide right on the product page (the correct chart for that category or brand), and ideally make it interactive so the shopper can confirm their fit. dfsizeguide bundles all three: an EU/US/UK chart editor, a smart assignment system that picks the right chart automatically, and a calculator that turns measurements into a recommendation.
How the chart resolver works
When a customer lands on a product page, the module runs a top-down priority lookup: first it checks for an explicit assignment on this product, otherwise for its manufacturer, otherwise for any of its categories (deepest first to respect specificity), and finally falls back to the chart marked as the global default. Merchants can therefore maintain a single chart per brand or per department without touching individual product sheets.
The size calculator in detail
Customers enter their measurements (chest, waist, hips, foot length depending on the chart). The algorithm normalizes the values to centimeters (automatic conversion when the user picked inches), iterates over each row of the table, gives 2 points for a measurement that falls within the exact range and 1 point for a measurement close within plus or minus 5 percent. The size with the best score wins, and ties are broken by picking the row whose ranges are most centered on the customer's values. The top three candidates are displayed, with the recommended row highlighted in the table.
Seven positions to fit any theme
Every PrestaShop theme places product-page elements differently. The module exposes seven checkboxes in the back office, each mapped to a hook: clean tab via displayProductExtraContent (the recommended default), under price, near the Add to cart button, under product info, in the reassurance block, after the images, or at the bottom of the page. Enable them alone or in combination; the modal markup is shared (anti-DOM-duplicate), and three visual button variants (compact, prominent, reassurance) are applied automatically based on the chosen position.
Customer feedback: turning each purchase into a quality signal
The post-purchase feedback widget is rendered only for logged-in customers who actually bought the product and have not yet responded. Five choices: too small, a bit small, perfect, a bit large, too large. The back office aggregates everything in a table with an automatic bias score: positive when the product consistently runs large, negative when it runs small. This lets you identify badly graded references to fix on the supplier side, or to manually switch to a more generous chart.
SEO: capturing size-related searches
The module exposes a dedicated page per category via PrestaShop's moduleRoutes system, at a configurable URL such as /size-guide/women. The page features an h1 title, breadcrumb, the full chart, measurement instructions and a JSON-LD WebPage markup that helps Google understand the page is a practical guide. Per-chart meta title and description are configurable. Perfect for ranking on long-tail queries like "women dress size guide" or "men shoe size conversion".
There are no reviews yet.