Build a size guide

A size guide turns a shopper's measurements into one of your sizes. It uses only your chart (or quick grid) and the rules you set: no generic body models, no hidden defaults. Open Size finder in the app menu, then New size guide, and start from a template or a blank chart.

Template values are examples. Replace them with your own chart before you publish; until you edit a value, publishing asks you to confirm them.

Building a chart#

The Chart tab has one row per size (smallest first) and one column per measurement.

• Type each cell as a range (80-87), a single value (86), or an open end on the first or last size (<60, 120+). Comma decimals work (80,5).

• A column is all ranges or all single values. Single values become ranges at the midpoints between sizes.

• Show values in switches the display between cm and inches. Values are always saved in cm (kg for weight).

• Add, remove and reorder sizes with the buttons on each row, and measurements with + Measurement and the buttons under each column name.

Click a column's name to open its measurement settings: what it measures, where (natural or low waist; chest or under the arms), full or half, its role, and its ease.

Roles#

• Primary: decides the size. A chart has exactly one.

• Must fit: moves the size up when it needs a larger one.

• Secondary: shown to the shopper as a check; it never changes the size.

Half vs full#

Most charts give body measurements all the way around (full). Some garment charts measure across the garment, laid flat (half): 50 cm across is 100 cm around. Set such a column to half and the size finder doubles it.

If a full column's values look like half measurements (below what any adult measures, but plausible when doubled), the checks say so.

Garment ease#

Choose Garment measurements when your chart measures the clothes, not the body. A garment is bigger than the body that fits it; that difference is the ease. Enter each measurement's ease in cm (the Ease row): the size finder subtracts it to get the body range. For stretch fabric with no ease, tick Stretch fabric, no ease in the measurement settings. Negative ease is allowed for garments smaller than the body.

Quick grid#

The Quick grid tab sizes by one or two inputs, like height × weight, or a choice like the dog's breed. Each axis is a measurement in ranges (each range runs up to, not including, its end; the last includes it) or a list of options. Suggest a cut splits a range you type into even parts. Pick a size for each cell; Empty cells answer sets what an empty cell gives.

Rules and presets#

The Rules tab decides what happens when measurements disagree or fall between two sizes.

• Presets (tops, bottoms, men's trousers, dresses, wovens, knits) fill in the rules, and for some the roles, visibly: check what they set and change anything that doesn't fit your products.

• When measurements disagree: the primary decides (a must-fit can move it up), or the largest size any must-fit measurement needs.

• Between two sizes: size up or down. A value within the edge band of the line between two sizes counts as between them.

• Fit preference: let shoppers pick slimmer or relaxed; it shifts circumference measurements by the amounts you set, and decides between two sizes first.

• Fit note (runs small, runs large): decides between two sizes before the size-up or size-down rule.

• Too far apart: when a must-fit measurement needs a size this many steps from the primary's, no size is suggested.

Shopper text#

Set the title, an intro, and a hint per measurement (leave a hint empty to show the default). Every guide needs a fallback for shoppers no size fits: the size chart on the product page, a link to your own size guide, or a short text.

In a store with several languages, choose a language on the tab and write the title, intro, hints and fallback text for each one (see Languages). Changes reach shoppers when you publish the guide again.

Before you publish, read the checks and try the tester: see Check and test a size guide.

Which products use a guide#

The Products tab decides which products use the guide. Add rules by tag, collection, product type, vendor or individual product; a product matches when any rule does. Each product uses one guide: the first in your size guide list (the arrows on the size finder page) whose rules match it. The count under the rules shows how many products they match before you save. Rules apply when you Save rules, and new or changed products in Shopify follow within a minute or two.

The table lists every product using the guide with its state:

• Ready: on sale, published to your online store, the guide is published, and at least one of its sizes maps to the product's options.

• No size option: the product has no option with the name the Mapping tab uses.

• Not mapped: none of the product's option values maps to a size (the reason lists them).

• Not on sale: a draft or archived product, or one not published to the online store.

• Guide not published: publish the guide first.

The size finder page lists Products without a size guide: active products with a size option (Size, Taille, Größe, Talla, …, or a name a guide maps) that no guide's rules match.

Mapping sizes to your options#

The Mapping tab says which option value each size is. Name the option (usually Size; two options for a size made of two parts, like Band and Cup) and any other names products use for it (Taille). Then give each size its value(s). Accept suggestions fills in the sizes Quizproof matched for you: the same text (M = M), the same size spelled differently (XXL = 2XL), or a size's name (S = Small). A mapping between sizing systems (M = 38) is never suggested: add it yourself if it is right for your products.

A size can have several values, in order: a product uses the first one it has. Use this when products spell a size differently, or for a second system (M, then 30 for jeans). The products list shows values no size maps to; they aren't offered to shoppers. Publishing stops if a value has the wrong number of parts for the options, and warns when no product would be ready or some values aren't mapped.

Publishing#

Publish freezes the draft as the next version; earlier versions stay as they were. Discard draft puts the live version back as the draft. Archive takes a guide out of use; an archived guide can be deleted. A deleted guide disappears at once, and its versions are kept until no product or open shopper session uses them.

Every ready product is then published to your store in the background, so your product pages can show the guide without slowing down. The guide's page and Size finder show how far it got: "Live on 42 products · publishing 120 / 3,000 · 1 error". The Products tab shows each product as Published, Publishing, Error or Not published (a product that isn't ready). A product that couldn't be published is listed with the reason; it is tried again every few minutes, and Retry tries now. A new version replaces the old one product by product, so a page never mixes two versions.

Add the block#

Shoppers find their size with the Find my size block on your product page.

1. Open Size finder and choose Add to product page on the card "Add Find my size to your product page". The theme editor opens on your product template with the block added.

2. Drag the block right under the size picker (the variant picker).

3. Save.

You can also add it yourself: in the theme editor (Online Store › Themes › Customize), open your product template and add the Find my size app block to the product section. The block works on product templates only. We have tested it on Dawn, Horizon and Spotlight (Apps that work with Quizproof).

Back in Quizproof, the card is gone, and Home counts the block ("Find my size blocks placed").

Shoppers then see a Find my size button. It opens a short dialog that asks for their measurements, tells them their size and why, and selects that size on the product page. Under the button, your Size chart opens in place.

The block shows only on products that use a published size guide. Without JavaScript, or at 120% of your plan's completions, it shows your size chart (or your guide's link or text) and no button.

Size finder settings#

Settings › Size finder sets:

• Default units: Automatic (by the shopper's country: the US, Liberia and Myanmar get inches and pounds, everyone else centimetres and kilograms), Metric or Imperial. Shoppers can switch in the dialog.

• Text: every word on the button and in the dialog, for each language your store publishes: choose the language first. An empty field shows the built-in text in that language. Placeholders in braces, like {size}, are filled in for each shopper; some must stay in. Each language's text together can be up to 2,048 bytes.

Import and export#

Bring your chart in. New size guide › Paste takes a table copied from a spreadsheet or a web page, and Upload CSV takes a .csv file (up to 256 KB; commas, semicolons or tabs; UTF-8 or UTF-16). On a guide, Replace from paste or CSV swaps its chart or quick grid for the table. Quizproof reads:

• ranges like 80-87, 80–87, 80 to 87, open ends like <60, up to 60, 120+, 120 and up;

• comma decimals (80,5), fractions (33½, 33 1/2) and feet and inches (5'7");

• units from the headings (Chest (cm), Waist in, Weight (lbs)); without one, the unit you choose for the table. Inches and pounds are stored as cm and kg, to 0.1;

• headings in English, German, French, Spanish, Italian and Dutch (Chest, Brust, Poitrine, Pecho, …). A heading it doesn't know asks you what the column measures, or you can leave the column out.

Nothing is saved until you apply it. The preview shows every value as read, in cm, with the text it came from; values it can't read are red and stay empty. Check the detected shape (chart or quick grid), switch Swap rows and columns when your sizes run along the top, and accept the flat (half) suggestion on columns like "Chest width (flat)". The checks for the result show before you apply, and publishing waits until they pass.

Export. Download CSV on a guide saves its chart (and its quick grid as a second …-grid.csv file); both read back in to the same values. Export all on the size finder page saves every guide (its draft and its live version, its rules and its mapping) and your size finder settings as one .json file.

Import an export file. Import export file adds the file's guides as drafts, here or in another store. Nothing you have is changed or published: a name that's taken gets " (imported)", and a guide whose draft differs from its live version comes in as two drafts (<name> from the live version, <name> (draft) from the draft). Rules that name a collection or a product find it here by its handle; one this store doesn't have is left out and listed in the report. Your settings change only if you tick Also replace my size finder settings. A store holds up to 200 size guides, and an export file can be up to 16 MB.

How size-finder runs count#

A shopper's "Find my size" run on a product page counts as one completion, like a quiz: your plan's limit covers quiz or size-finder completions, and the plan page shows how many of this period's were size finder runs ("of which size finder"). A run counts once, at its first result (a size, "outside the chart", or "no size fits"). Changing the answers, reopening it within 30 minutes, missing or invalid measurements and your own tests in the editor are free. Runs from automated browsers count apart, as other suspicious completions do.

At 120% of your plan's completions, new runs stop and the block shows your guide's fallback instead: its size chart, or its link or text when it has no chart. A run that already started still finishes, and remembered sizes still show. See Plans and limits.

Remembered sizes#

When a shopper has allowed preferences in your store's cookie banner, the size finder remembers their measurements on their device after a counted run. On every other product page with the block they then see Your size: M · change right away, without opening the dialog, and Select M when the page shows another size. The size is worked out again for each product's own guide, so a sweater and a dress can give different sizes from the same measurements. Remembered sizes are free: they never count as completions, and they still show at 120% of your plan (with Select, but no change).

• Where it's stored: only in the shopper's browser (local storage, quizproof:size): their measurements, their grid answers, their fit preference, any "Select L instead" they picked on a product, and an expiry 180 days after their last run. Quizproof's servers keep none of it; they only check the signature that proves a counted run made it.

• Consent: nothing is saved without preferences consent (where your privacy settings ask for no consent, Shopify counts preferences as allowed). If the shopper later declines preferences, the saved sizes are deleted.

• Forget: Forget my size (on the product page and in the dialog) deletes them at once. In the dialog, This is for someone else, don't save runs the finder without saving.

• If a product needs a measurement the shopper hasn't given (a dress that also needs the hip), it shows the usual Find my size, and the dialog opens with what's already known filled in.

• After you change a guide and publish it, remembered sizes are worked out again with the new chart. A "Select L instead" pick stays until that product's sizes or mapping change.

Privacy#

• Measurements: used only to work out the size. Quizproof's servers don't keep them. A run keeps its result (the size given, or why none was) for 90 days, with no measurements and nothing that identifies the shopper.

• Remembered sizes: only in the shopper's browser, and only with preferences consent (see above).

• Analytics: the size finder sends its funnel events only while the shopper allows analytics in your cookie banner. The events hold no measurements and no shopper identifiers, and are kept 90 days. The daily totals behind the card below are kept as long as your store's data.

More in Privacy and consent.

Languages#

Shoppers see the size finder in your storefront's language. Quizproof has built-in text in English, German, French, Spanish, Italian, Dutch, Portuguese, Polish, Swedish, Danish and Japanese: the button, the dialog, results, measurement names and how-to-measure hints, and the size chart's caption and headings. Portuguese is one Brazilian Portuguese text, used for stores in Portuguese (Brazil) and Portuguese (Portugal).

The built-in translations were drafted by an AI model and reviewed by a second AI model. Read them in your languages and change anything that doesn't sound right for your store.

A shopper sees the text for their storefront language, else your store's primary language, else English. Your own text comes first in each language:

• Settings › Size finder › Text: the button and dialog text, per published language (up to 2,048 bytes each).

• The guide's Shopper text tab: its title, intro, hints and fallback text, per language. Publish the guide again for the change to reach shoppers.

The chart shows decimal commas where the shopper's language uses them (80,5). Quizproof reads your store's languages from Shopify; if you installed Quizproof before the size finder, Shopify asks you once to approve this access.

The size finder's numbers#

Size finder shows a Last 30 days card with each guide's funnel. The numbers update every hour, with your other analytics.

Stopped here is how many runs went no further than that step. Under the funnel:

• Select rate: runs that selected a size, out of runs that got a result.

• Override rate: shoppers who then picked another size, with Select L instead or by changing the size on the product page after selecting, out of runs that selected a size.

• Entered, of runs that chose how to measure: how often each measurement was filled in.

• Last result per run and Sizes given: the outcome mix and the size mix.

• Remembered size: how often the Your size line was shown, and how often its Select was used.

The card counts only shoppers who allowed analytics, so it shows fewer runs than your plan: "Counts only shoppers who allowed analytics. Size-finder runs on your plan this period: N". The plan counts every run that reached a result, whatever the shopper's cookie choice.

Reading it honestly. The size finder helps shoppers choose a size. Watch the select rate (do shoppers take the size it gives?) and the override rate (do they then pick another?). A high override rate on one guide is worth a look at its chart, rules and mapping. Don't expect a returns percentage from it: the card doesn't measure returns, and Quizproof makes no promise about them.