How to Translate Shopify Size Charts and Units of Measurement for International Markets

A German shopper who buys a US size 10 shoe expecting a European 43 is going to return it — and probably never come back. Getting Shopify size chart translation right is one of the highest-ROI localization tasks you can do, because it directly cuts return rates and removes a real buying barrier without requiring you to change a single product.

This guide covers exactly how to do it: where size chart content lives in Shopify, which units need converting (not just translating), and how to keep everything in sync as your catalog grows.

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Why Size Chart Translation Is Different From Regular Translation

Most Shopify translation work is about language: turning English words into French or Japanese. Size charts are a layer harder — they require unit conversion as well as language translation, and the rules vary by market, product category, and even gender.

A few examples of what "translation" actually means here:

• Clothing sizes: US "Small / Medium / Large" vs. EU numeric sizes (36, 38, 40) vs. UK sizes vs. Italian numeric vs. Korean alpha-numeric. These are not the same — they require a conversion table, not just a word swap.
• Shoe sizes: The US men's, US women's, UK, EU, and Japanese systems are all different scales. A US men's 9 is a UK 8, EU 42.5, and JP 27.
• Measurements: Chest, waist, and hip measurements are in inches for US/UK shoppers and centimetres for most of the rest of the world.
• Weight: Pounds vs. kilograms matter for luggage, sports equipment, and pet products.
• Ring sizes: US numeric, UK alpha, French/German numeric, Japanese numeric — four completely different systems.

None of this can be handled by a simple word-for-word translation. You need a deliberate localization strategy.

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Where Size Chart Content Lives in Shopify

Before you can translate anything, you need to know where the content actually is. Size charts typically appear in several places:

1. Product Descriptions

The most common place. Many merchants paste a size chart table directly into the product description as HTML. This is translatable via Shopify's translation API — and tools like StoreLingo translate this content at the product level, so you can review and publish per language.

2. Metafields

Increasingly, merchants store size charts in a dedicated metafield (e.g., product.metafields.custom.size_chart) and surface it via their theme. Metafields are translatable in Shopify, but not every translation app handles them. If yours does, this is actually the cleanest approach — one metafield per language, easy to update. See How to Translate Shopify Metafields, Metaobjects and Custom Data for a full walkthrough.

3. A Dedicated Page or Popup

Some themes link to a "Size Guide" page or trigger a popup modal. The page content is translatable like any other Shopify page. The popup trigger text (a button or link) lives in your theme's locale files. Both need attention — see How to Translate Shopify Theme Content: Buttons, Navigation and System Text.

4. App-Injected Content

If you use a third-party size chart app, its content may not be accessible to Shopify's translation API at all. Check How to Translate Shopify App Blocks and Third-Party Widget Content for International Stores — this is a common gap that merchants miss entirely.

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How to Approach Unit Conversion by Market

Translation handles the language. You need a separate step for unit conversion. Here's a market-by-market breakdown of what to change:

United States

• Measurements: inches
• Weight: pounds (lb) and ounces (oz)
• Clothing: US sizing (XS–XL or numeric)
• Shoes: US men's / US women's scale

United Kingdom

• Measurements: mostly centimetres for clothing, inches for some contexts
• Clothing: UK sizing (close to US but not identical — a US 12 dress is a UK 16)
• Shoes: UK scale

Europe (Germany, France, Italy, Netherlands, Nordics)

• Measurements: centimetres exclusively
• Clothing: EU numeric sizes
• Shoes: EU scale
• For Germany specifically, see How to Localize Your Shopify Store for the DACH Region

Japan and South Korea

• Clothing often uses Japanese numeric sizing (5, 7, 9, 11) or Korean sizing in cm (e.g., 85, 90, 95 for chest)
• Shoes: JP cm-based scale (e.g., 25.5 cm) or Korean mm-based
• Details for Japan: How to Localize Your Shopify Store for Japan; for Korea: How to Localize Your Shopify Store for South Korea

Middle East

• Generally follows EU sizing but with regional brand familiarity differences
• RTL languages (Arabic) affect table layout — see Selling in RTL Languages: Arabic & Hebrew on Shopify

Brazil / Latin America

• Brazilian sizing uses numeric (P, M, G, GG or 36–46) — similar to EU but with local variation
• Measurements in centimetres

The practical recommendation: maintain a master conversion table outside Shopify (a spreadsheet works fine) mapping your source sizing to each target market. Use this as the source of truth when writing your translated size chart content, rather than relying on AI to infer the conversions.

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The Right Workflow for Shopify Size Chart Translation

Here's a practical step-by-step process:

1. Audit where your size charts live — product descriptions, metafields, pages, or third-party apps.
2. Build your conversion table — map your base sizes to every target market before touching Shopify.
3. Rewrite the content per locale, not just translate it — for EU markets, don't translate "chest: 38 inches" into French and leave the inches. Replace the value: "poitrine : 97 cm."
4. Use a translation app that handles product-level content — tools like StoreLingo translate product descriptions (where most size charts live) and flag changed content for re-translation when you update them, so a size chart update doesn't silently go stale in a foreign language.
5. Review before publishing — size chart errors are high-stakes. Use your translation tool's review workflow to check converted values, not just translated words.
6. Protect consistent terminology — if you call it "Size Guide" in English, use a glossary to ensure it's consistently "Guía de tallas" in Spanish and "Größentabelle" in German across every product. StoreLingo's built-in glossary feature handles this automatically. Learn more in How to Use a Translation Glossary to Protect Brand Terms Across Your Shopify Store.
7. Keep translations in sync — when you update a size chart (new season, new product line), your translated versions need updating too. How to Keep Your Shopify Translations in Sync as Your Catalog Changes explains how change detection works.

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Common Mistakes to Avoid

• Translating units instead of converting them. "38 Zoll" (38 inches in German) is technically translated but practically wrong and confusing.
• Using one size chart for all European markets. Italian, French, German, and UK sizing have small but meaningful differences, especially in footwear.
• Forgetting the size chart popup button. You translate the chart but leave "View Size Guide" in English — shoppers don't click it.
• Ignoring RTL layout for size tables. Arabic and Hebrew tables need column order and alignment checked manually.
• Not updating translations after a product refresh. This is where automated change detection pays for itself.

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FAQ

Does Shopify automatically convert units of measurement when I enable a new language? No. Shopify's native multilingual features translate text through the Translations API but do not perform unit conversion. You need to manually provide the correct converted values (e.g., centimetres instead of inches) in each language's content.

Can I use AI translation for size chart content, or does it need to be done manually? AI translation handles the language layer well — turning "chest measurement" into "tour de poitrine" — but it cannot reliably infer the correct unit conversion without guidance. The safest approach is to pre-convert your numeric values in a spreadsheet and then use AI translation for the surrounding text, or write the converted content per locale and let AI translate the labels.

What's the best place to store size charts in Shopify for multilingual stores? A dedicated metafield (e.g., custom.size_chart) is the cleanest solution — it keeps size chart content separate from the product description, makes it easier to update per locale, and is accessible to Shopify's translation API. If your translation app supports metafield translation, this approach scales well as your catalog grows.