How to Add a Size Chart to Shopify (and Cut Returns)

Why Size Charts Stop Returns Before They Happen

Sizing issues are the #1 driver of e-commerce returns — and they hit your bottom line twice: you lose the sale AND eat return shipping. A clear, accessible size chart solves this at the moment of purchase, when shoppers are still decide. In this guide, you’ll learn exactly how to add a size chart to Shopify using the most practical methods, with a focus on tools that actually cut return rates.

Add a Size Chart with a Dedicated Shopify App

The fastest, most flexible way to get a professional size chart on your store is through a dedicated app. While Shopify’s basic themes let you add static content, dedicated size chart apps give you dynamic tables, fit recommendations, and the ability to swap charts per product — without touching code.

One option worth considering: the Kiwi Sizing app (also found as a shopify app kiwi size chart solution) offers customizable charts plus AI-powered fit recommendations. This combo — static charts plus smart recommendations — addresses both the “what size am I?” and “will this fit?” questions shoppers have. Many store owners specifically search for kiwi size chart shopify app solutions because the tool handles both sizing tables and personalized fit guidance in one place.

• Install directly from the Shopify App Store
• Choose from chart templates or build custom tables
• Enable “size recommender” popups that ask simple fit questions
• Works across all product types: apparel, footwear, accessories

Step-by-Step: Setting Up Kiwi Size Chart

Here’s how to get a size chart live on your store in under 15 minutes:

1. Install the app — Search “Kiwi Sizing” in the Shopify App Store or go directly via the kiwi size chart & recommender shopify listing. Install and grant it theme access.
2. Create your first size chart — In the app dashboard, click “New Size Chart.” You can upload an image, build a table manually, or import from CSV if you have sizing data already.
3. Assign to products — Select which products or collections should display this chart. You can create multiple charts (one for tops, one for pants, one for shoes) and map them automatically based on product tags or types.
4. Add the button to your theme — Most apps including Kiwi provide a “Size Guide” button you can place near the “Add to Cart” button. The app gives you a snippet or automatically inserts it depending on your theme.
5. Test on mobile and desktop — Open a product page and verify the chart opens as a popup or inline. This is critical — over 60% of apparel purchases happen on mobile.

What Makes a Size Chart Actually Work

Adding a chart isn’t enough — it needs to be readable, accurate, and easy to find. Here’s what separates charts that cut returns from ones that get ignored:

• Show measurements, not just sizes — Include chest, waist, hip, and length dimensions in both inches and centimeters. Shoppers who between sizes need exact numbers.
• Add fit guidance — If a garment runs small, note it. If it’s oversized, say so. This is exactly what the kiwi size chart & recommender feature automates — it asks buyers about their height, weight, and preferred fit, then suggests a size.
• Use visuals — A diagram showing where each measurement is taken beats text alone. Most size chart apps include placeholder images you can replace with your own.
• Link it prominently — Place the “Size Guide” link right next to the size selector dropdown. Don’t bury it in the footer.

Going Beyond the Basic Chart: Smart Fit Recommendations

If you’re serious about reducing returns, a static chart solves part of the problem. The other part: shoppers who still aren’t sure what to pick. That’s where AI-powered recommendations come in.

When you enable the recommendation engine (included with Kiwi Sizing), shoppers answer 2-3 quick questions — “What’s your usual size in other brands?” or “Do you prefer a snug or loose fit?” — and the tool suggests the best option. This removes the anxiety of guessing. Stores using this kiwi size chart approach typically see a 10-25% drop in sizing-related returns, because buyers are making more informed choices before checkout.

This is the key differentiator between a basic shopify size chart and a complete fit solution. You’re not just giving information — you’re actively helping the shopper decide.

When to Use Manual Methods (And Why Apps Are Better)

You can technically add a size chart by editing your theme code or using Shopify’s “Custom Liquid” block. This works if you’re comfortable with HTML/CSS and only need one chart for your whole store. But it falls apart when:

• You sell multiple product types (you’d need separate charts for shoes vs. shirts)
• You want to update charts regularly (sales, new inventory)
• You want to track which sizes are most commonly returned

Dedicated apps handle all of this with a few clicks. For most Shopify stores, the app route saves hours and pays for itself within weeks through fewer return processing costs.

Measuring Results: Did Your Size Chart Actually Help?

After you’ve had your chart live for 30 days, check these numbers:

• Return rate for sizing issues — Compare month-over-month. A solid chart should drop this by 15%+.
• Size guide clicks — Most apps track this. If click-through is low, move the button to a more visible spot.
• Fit recommendation uptake — If you enabled the recommender, see what % of shoppers use it. High usage = high value.

If returns aren’t budging, audit your chart for missing measurements or unclear fit notes. The issue is usually content, not the tool.

Does every product need its own size chart?

Not necessarily. If all your products follow the same sizing scale (e.g., you only sell one brand of t-shirts), you can use a single global chart. But if you sell varied items — like denim, outerwear, and activewear — each category likely needs its own chart because sizing standards differ drastically between types.

Can I use a size chart app with a custom Shopify theme?

Yes. Most size chart apps, including Kiwi Sizing, work by injecting a button and modal into any theme. You may need to manually place the button snippet in your theme code if the automatic placement doesn’t match your layout, but the app provides clear instructions for this.

Will a size chart slow down my store page load time?

Quality apps load the chart data only when someone clicks “Size Guide,” so there’s minimal impact on initial page load. If you’re concerned, test your store speed with Google PageSpeed Insights before and after installing.

Recommended apps for this

The tools we’d reach for — each links to its Shopify App Store listing.

Kiwi Sizing

★ 4.8

Kiwi helps you remove any sizing uncertainty with customizable size charts and AI-powered fit recommendations that guide shoppers…

Try Kiwi Sizing →

Partner links — you pay the same price as going direct via the Shopify App Store. App details and pricing change; verify on the live listing before installing.