> For the complete documentation index, see [llms.txt](https://sitesbyseth.gitbook.io/sitesbyseth-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://sitesbyseth.gitbook.io/sitesbyseth-docs/skeleton/size-finder.md). # Advanced The size finder is Skeleton's answer to "will it fit?" — the single biggest reason clothing shoppers hesitate. A customer taps **Find your size** on a product page (or in quick view), enters height and weight in metric or imperial, and gets a size recommendation calculated from **your** size chart and how **that piece** fits. Their result is remembered and shown as a small badge on every Find your size link afterward. This page covers the chart format, fit profiles, garment types, per-product size charts, and — in plain words — how the math works. ## The chart format Everything starts with one setting: **Theme settings → Size finder → Size chart (measurement limits)**. One size per line, three values separated by commas: ``` S,170,65 M,178,80 L,186,95 XL,999,999 ``` Each line means: **size name, max height in cm, max weight in kg**. * `S,170,65` — S fits customers up to 170 cm tall and 65 kg. * Lines must go from smallest size to largest. * Use `999` on your largest size to mean "no upper limit." * Size names should match your product variant sizes (S, M, L, XL, 2XL…). The finder understands common spellings — "Small," "SM," "2XL," "XXL" are all recognized. **Where do the numbers come from?** Take each size's garment measurements and ask: what's the tallest, heaviest person this still fits comfortably? If you don't have fit-test data, start with the defaults above (a standard men's streetwear curve), sell a few weeks, and adjust from exchange requests. ⚠️ If the box is empty or the lines don't have three comma-separated values, the finder has nothing to work with and shows "No matching size found — check the size chart." ## Fit profiles A fit profile tells the finder how a piece is cut relative to the chart: * **True to size** — no adjustment. * **Runs small — recommend sizing up** — nudges the recommendation up by three-quarters of a size. * **Runs large — recommend sizing down** — nudges down by three-quarters of a size. * **Oversized / relaxed fit** — nudges down a full size, since the garment already carries extra room. Set the store-wide default under **Theme settings → Size finder → Default fit**, and override per product template on the **Find your size** block (**How this piece fits**). When an adjustment was applied, the customer sees a note like "Adjusted down — this piece runs large" under their result, which builds trust in the number. ## Garment types The garment type controls how much **height** matters relative to **build**: * **Tops / tees / hoodies** — length matters a lot: a tall, slim customer is pushed up a size so sleeves and hem are long enough. * **Bottoms / pants** — length pulls only gently (inseams are often hemmed anyway); waist/build dominates. * **Outerwear / jackets** — like tops. * **Dresses / one-pieces** — length matters most of all. Default under **Theme settings → Size finder → Default garment type**; per-product override on the **Find your size** block. ## How the math works, in plain words The finder estimates two separate demands and blends them: 1. **Girth (chest/waist)** — the main driver of whether a garment fits. It's estimated two ways and averaged: from the customer's weight against your chart's weight limits (65%), and from their BMI — weight adjusted for height — mapped onto a universal XS–3XL curve (35%). The BMI part stops a tall-but-slim customer from being treated like a heavy one. 2. **Length** — the customer's height against your chart's height limits. Then the blend is deliberately lopsided: a garment **must** accommodate girth, so when the body is long for its build, length pulls the size **up** strongly (tall + slim → size up so it's long enough), but when the body is short for its build, it pulls **down** only slightly (short + broad still needs the girth). How strong that pull is depends on the garment type above. Finally: * The fit profile shifts the result (e.g. −1 size for oversized). * The result rounds to the nearest size on your chart. If it lands just under a size boundary, the customer also sees "You're between sizes — take \[the next size up] if you like it roomier." * The recommendation **snaps to sizes the product actually has**: if the math says M but this product only comes in S/L, the nearest real size wins (larger preferred). It only considers the product's size option, so sold-out or nonexistent sizes are never recommended. Height must be 120–230 cm and weight 30–250 kg — anything outside that gets "Enter your height and weight" rather than a junk recommendation. Imperial users type weight in pounds and height as feet-inches (typing `511` auto-formats to `5'11`); the theme converts internally. ## Per-product size charts (the metafield) Besides the calculator, the modal has a **View size chart** button that shows a chart image. There are two levels: * **Global charts** — up to three stacked images (plus an optional page) under **Theme settings → Size finder**. Shown for every product that doesn't have its own chart. * **Per-product chart** — an image on the product's `custom.size_chart` metafield. When present, it **replaces** the global images for that product. To set up the per-product metafield (once): 1. In your Shopify admin, go to **Settings → Custom data → Products**. 2. Click **Add definition**. 3. Name it **Size chart**. Click the **Namespace and key** field and set it to exactly `custom.size_chart`. 4. Set the content type to **File**, and accept image files. Save. 5. Now open any product (**Products → your product**), scroll to the **Metafields** section at the bottom, and upload that product's chart image into **Size chart**. Products with no per-product chart and no global chart simply don't show the View size chart button — the calculator still works. 💡 The measurement-limits chart (the `S,170,65` lines) is one global setting — it doesn't change per product. The per-product metafield changes only the chart **image**. If different product types need genuinely different curves (e.g. numbered pant sizes), lean on the garment type + fit profile overrides, and put the detailed numbers in that product's chart image. ## Quick test before launch 1. Open a product, tap **Find your size**. 2. Enter 178 cm / 75 kg → with the default chart you should see **M**. 3. Enter 191 cm / 71 kg (tall and slim) → the recommendation should move up, not down. 4. Switch to Imperial, type `511` and 165 lb → same ballpark answer. 5. Check the **View size chart** button shows the right image on a product with a metafield chart, and the global one elsewhere. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. 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