RMS Size Helper vs ZG Size Guide & Fit Finder
Two Shopify apps, side by side: detected stores, momentum, reviews, plans, listed features and who runs each. Store counts as of Oct 13, 2026.
The short answer
- Both list a free plan. Paid plans start at $9/month for RMS Size Helper and $9.99/month for ZG Size Guide & Fit Finder.
- ZG Size Guide & Fit Finder lists 17 features RMS Size Helper’s listing doesn’t mention, including AI recommendations, Analytics, Comparison table.
Head to head
Free
- · 1 with Size Helper
- · 30-day analytics
- · 50 recommendations/month
- · Default button styling
- · RMS branding shown
- · Up to 3 size charts
Growth
- · 10 with Size Helper
- · 500 recommendations/month
- · 90-day analytics
- · Custom button colours
- · No RMS branding
- · Per-product analytics
Professional
- · 1-year analytics
- · 35 with Size Helper
- · Custom button colours
- · No RMS branding
- · Per-product analytics
- · Priority support
Enterprise
- · Custom button colours
- · No RMS branding
- · Per-product analytics
- · Priority support
- · Unlimited Size Helpers
- · Unlimited analytics retention
Free
- · 3 size charts
- · 7-day analytics
- · Built-in storefront UI translations in 9
- · Product and tag assignment rules
- · Table, image, and mixed chart formats
- · Template downloads
Pro
- · 90-day analytics
- · All assignment rules and global fallback
- · CSV / Excel import and export
- · Find-my-size wizard and brand offsets
- · Multi-chart tabs
- · Size-system conversion for shoes
Coverage counts what each App Store listing names. Every feature, checked off app by app, is in Shoplist.
See every featureYou know the email before you open it: "This didn't fit — how do I return it?" Each one costs you time, margin, shipping, and a hesitant customer. RMS Size Helper steps in before checkout: a few quick questions on measurements and fit preference, and shoppers get the right size in any sizing system, anywhere in the world. Fewer wrong-size orders, fewer refunds, more customers who buy once and never worry again.
ZG Size Guide & Fit Finder helps merchants create clear size charts, fit guides, and size recommendations for product pages. Use built-in templates, import CSV/Excel files, assign charts by product, tag, collection, vendor, category, gender, or region, and show multiple guides as tabs. Shoppers can compare measurements, switch CM/IN units, use shoe size conversion, and get a recommended size through the fit finder.
- Smart "Find My Size" survey guides customers to their perfect fit.
- Create custom size templates for tops and bottoms with international sizes.
- Choose between "Size Chart + Size Helper" or "Size Chart Only" size guides.
- Assign size templates to individual/multiple products and groups.
- Create size charts from templates for common apparel types
- Recommend sizes using shopper measurements and fit preference
- Show shoe size equivalents for US, UK, EU, Japan, and store sizing
- Show multiple fit or length guides as tabs on one product page
All the numbers
Every figure, side by side
A green dot marks the app ahead on a measured figure. Estimates, gaps and apps that leave no storefront trace never take the lead.
Adoption
| Measure |  RMS Size Helper |  ZG Size Guide & Fit Finder |
|---|---|---|
| Detected stores | Not published | Not published |
| Net store change, 28 days | 0 | 0 |
| Stores added, 28 days | Not enough data | Not enough data |
| Big-brand share | Not enough data | Not enough data |
| Top store categories | Not published | Not published |
| Top store countries | Not published | Not published |
Reviews
| Measure | RMS Size Helper | ZG Size Guide & Fit Finder |
|---|---|---|
| App Store rating | Not published | 5.0 ★ |
| App Store reviews | Not published | 1 |
| New reviews, 28 days | Not enough data | Not enough data |
| Reviewers a year or more in | Not enough data | Not enough data |
Pricing
| Measure | RMS Size Helper | ZG Size Guide & Fit Finder |
|---|---|---|
| Free plan | Yes | Yes |
| Lowest paid monthly plan | $9/month(ahead) | $9.99/month |
| Longest free trial | 7 days | 14 days |
| Plans listed | 4 | 2 |
Listing
| Measure | RMS Size Helper | ZG Size Guide & Fit Finder |
|---|---|---|
| Shopify category rank | #197 | #131(ahead) |
| Shopify App Charts | Not on this week’s charts | Not on this week’s charts |
| Built for Shopify | No | No |
| Launched | May 8, 2026 | May 11, 2026 |
| Languages | 1 | 1 |
| Developer | RMS | ZEROGRAVITYCO LIMITED |
FAQ
RMS Size Helper and ZG Size Guide & Fit Finder: common questions
- Is RMS Size Helper or ZG Size Guide & Fit Finder cheaper?
- Both list a free plan. Paid plans start at $9/month for RMS Size Helper and $9.99/month for ZG Size Guide & Fit Finder. Shoplist compares base prices only between monthly plans in the same currency; usage charges and annual plans vary, so check each plan’s limits.
- What features does each app list that the other doesn’t?
- ZG Size Guide & Fit Finder lists 17 the others don’t mention, such as AI recommendations, Analytics, Comparison table, Custom icons. A feature missing from a listing may still be supported; this compares what each App Store listing says.
- Where does this comparison’s data come from?
- Shoplist crawls Shopify storefronts to detect which apps each store runs, and reads each app’s Shopify App Store listing for reviews, pricing, features and integrations. Store counts are as of Oct 13, 2026; estimated figures are labeled.
How Shoplist compares apps
Store counts come from Shoplist’s crawl of Shopify storefronts, which detects the apps each store runs; they are as of Oct 13, 2026. Reviews, ratings, plans, features and integrations come from each app’s Shopify App Store listing. 28-day figures are labeled when estimated, and a figure that is missing or estimated never decides who leads. Read the methodology.