SmartSize vs Theme Size Charts: Why Apps Offer a Better Sizing Experience for Fashion Stores
The Question
Many Shopify fashion themes come with a built-in size chart feature.
So — why install a dedicated app like SmartSize?
The answer depends on what kind of store you run, and how important sizing accuracy and user experience are to your sales.
Let’s break it down.
What Shopify Theme Size Charts Offer
Most popular fashion themes such as Dawn, Impulse, Prestige, Motion, and Streamline include a basic size chart option.
You’ll usually find it in the product template settings under:
Product Page → Size Chart → Enable Popup / Add Size Chart Image
Here’s what that provides:
| Feature | Description |
|---|---|
| Single Chart | One static chart that applies to all products. |
| Basic Display | A simple link or button (“Size chart”) opening a popup or modal. |
| Static Content | Usually an image or table hardcoded in your theme. |
| No Measurement Guides | You must add any measuring instructions manually. |
| Limited Customization | Button color, text, or placement may depend on theme layout. |
| No Multi-Language Support | You’ll need to duplicate content for each language. |
| Manual Maintenance | Updates require editing your theme code or metafields. |
For many stores — especially those with a small, consistent product range — this is enough.
The Limitations of Built-In Theme Charts
While convenient, theme size charts were designed to be simple placeholders, not data-driven tools.
Here’s where merchants start to outgrow them:
1. One Chart Fits All
Most themes only allow a single chart across the entire store.
That’s a problem if you sell different categories (tops, pants, dresses, shoes) or multiple brands with distinct sizing systems.
2. Hard to Update
If your measurements change, you must edit the chart image or HTML snippet in your theme editor — often across multiple templates.
Apps like SmartSize centralize updates: edit once, update everywhere.
3. Poor Mobile Experience
Many built-in popups use generic modals not optimized for tables.
Customers often need to pinch and zoom or scroll horizontally on phones.
4. No Measurement Instructions
Theme charts don’t include “How to Measure” guidance or diagrams.
As covered in our measurement guide article, missing instructions lead to incorrect self-measurement — and higher returns.
5. No Analytics or Tracking
You’ll never know how many customers open your chart, what products they viewed, or whether your sizing information helps conversion.
6. No Multi-Language or Unit Conversion
If you sell internationally, you must manually duplicate charts for cm/inches or English/French, increasing maintenance complexity.
7. Limited Design Consistency
Some themes force the size chart button to appear in the same spot or style as their default “share” or “wishlist” icons, which may not fit your brand aesthetic.
What SmartSize Adds on Top
SmartSize was built to handle all those gaps while keeping simplicity at the core.
| Feature | Theme Size Chart | SmartSize |
|---|---|---|
| Multiple charts per category | ✗ | ✓ |
| Multi-tab layout (e.g. measurements, fit notes, conversions) | ✗ | ✓ |
| Measurement instructions + images | ✗ | ✓ |
| Automatic cm/in toggle | ✗ | ✓ |
| Mobile-optimized table with fixed header | △ | ✓ |
| Multi-language support (Shopify Translate & Adapt) | ✗ | ✓ |
| Collection/product linking | ✗ | ✓ |
| Fit scale (runs small / large indicator) | ✗ | ✓ |
| Analytics (views per chart) | ✗ | ✓ |
| Live preview and editing | ✗ | ✓ |
| No coding needed | △ | ✓ |
Real Examples
Case 1: Small Boutique Using Dawn
If you sell only women’s t-shirts and hoodies with a single size range, the theme chart is fine.
Create a simple table or upload one image.
You probably don’t need an app yet.
Case 2: Expanding Brand with Multiple Categories
Once you add dresses, jeans, and jackets — all with different measurements — a single chart becomes confusing.
SmartSize lets you assign a different chart to each collection, so customers always see relevant information.
Case 3: International Fashion Store
If your store sells to both US and EU customers, SmartSize automatically shows sizes in both units and supports translations like “Size Guide / Guía de tallas.”
Themes can’t do this without custom coding.
When the Theme Option Is Enough
You might stick with your theme’s chart if:
- You sell only one product category.
- You rarely update sizing.
- You don’t sell internationally.
- Your return rate from sizing is low (<10%).
For these stores, built-in size charts are perfectly serviceable.
When SmartSize Makes a Difference
Switching to SmartSize makes sense if you:
- Offer multiple product categories or brands.
- Sell internationally (need cm/in + translations).
- Want professional design that matches your theme.
- Need to include “How to Measure” guides or visuals.
- Care about mobile usability and analytics.
- Want to test or optimize charts over time.
Final Thoughts
Shopify themes give you a great starting point.
But as your store grows, scaling sizing information manually becomes a bottleneck.
SmartSize automates this process with:
- Professional design and usability
- Centralized management
- International support
- Analytics to measure impact
If you’re running a small catalog, stay with your theme.
If you’re scaling or selling globally, upgrading to SmartSize saves time and prevents costly sizing returns.
▶ Tip:
SmartSize has a 14-day free trial to test out all its functionalities. If you are a small store, it includes 2 size charts completely free, forever.
Photo by Andrea Piacquadio: https://www.pexels.com/photo/woman-in-white-blazer-holding-tablet-computer-789822/