Calibre 9 | Master GMC Best Practices (Guide) | MAY 2025

Last Updated: 20 May 2025

INSTRUCTIONS

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TABLE OF CONTENTS

INTRODUCTION

Google Merchant Center

Google Merchant Center is a Google platform that allows businesses to upload all of the products they sell online and on location (brick-and-mortar) and manage their data so that they can appear across different Google surfaces.

Free Listings

One effective way to showcase your products for free is through Free Listings which allows you to share detailed information about your products, making it easier for shoppers to explore them. These listings provide a valuable, cost-free way to drive traffic to your online store and promote your business without ad expenses.

Eligible Free Listings can appear across various Google surfaces:

• The Shopping Tab

Free Listings appear below the Shopping Ads within the Shopping tab.

When you click on a Free Listing, it displays a Product Knowledge Panel that organises specific product info including product details, additional images, offers from different retailers, reviews, discussions, as well as related options. This can also be viewed from the SERPS.

• Search Results Page (SERPs) (+ Google Maps)

Within the SERPs, you can find Free Listings within Popular Product grids (the mobile version may also display subcategories), as well as other additional grids and features which we can expect more of to come.

If the merchant is subscribed to the Free Local Listings program, you may also be able to view products within the Google Business Profile knowledge panel,

In Store Nearby grids, Places map pack, and Products Nearby carousel.

• Google Images

Free Listings may appear within Google Images. They are usually represented by a tag label. Users may also view similar listings when they use the Google Lens feature.

YOUR GOOGLE MERCHANT CENTER ACCOUNT

How To Create A Google Merchant Center Account

Prerequisite:

Before you can sign up for a GMC account, you would first need to have a Google account. We recommend making one that’s unique to your business instead of using your personal account. (ex. calibrenine.webmaster@gmail.com)

Steps:

Advanced MCA accounts: What to do when you manage multiple/different stores

An advanced Multi-Client Account is recommended for businesses that manage multiple stores and domains at scale. Sub-accounts will become nested under this advanced structure and each sub-account can have distinct names, website URLs and data sources (feeds).

With this type of set up, you won’t need to create separate unique accounts for each business because the MCA is a "Manager" account used to organise merchants' sub-accounts (MC accounts). For example, if you own a family of companies, you can set up at MCA Account (which becomes the parent) that houses all your sub-accounts (for each business).

This set up is often recommended by Google to avoid being flagged for Misrepresentation especially if you have two or more stores that sell some of the same products. They recommend avoiding having multiple separate Merchant Center accounts that contain similar content as this could lead to account disapproval.

For example, if you have your main brand online store, but also have a separate online retailer store that sells your brand’s products among other brands’ products. Having separate Merchant Center accounts would put you at risk for getting account-level suspension. The solution would be to consolidate them by creating an advanced MCA account and housing the two stores as sub-accounts so that Google understands they are owned by the same merchant entity and not attempting to impersonate or misrepresent the other as the brand or business in user interactions.

Organising merchant sub accounts (MC accounts) with your Multi Client Account

Each merchant sub-account (MC account) can have a distinct store name and a unique website URL. The figure below demonstrates how you can organise one or more MCA: accounts for your merchants, who may have more than one online store, and in more than one country:

• Single Domains (such as myshop.com) under an MCA can be associated with separate Merchant Center subaccounts.

• Different Domains (such as us.myshop.com) and subdirectories (such as myshop.com/us) in that domain can use the same Merchant Center account.

• Separate domains (such as games.com, sneaker.com, myshop.fr and myshop.de) require a separate merchant account for each domain.

Follow these steps to request an advanced account set up.

How to provide Agency access to your existing GMC account

To add C9 or other users access to your existing Google Merchant Center account:

• Log in to your business Google account then navigate to https://merchants.google.com. Click the Gear icon in the top-right of your dashboard and select People and access.

• Select Add person under the People option. Enter our email address: calibrenine.webmaster@gmail.com then select Next.

• Ensure to provide us with Admin/Super Admin access. And click Add user. An invitation will be sent to us to accept.

• C9 has now been added to your Google Merchant Center account!

*To add other users, just follow these same steps and change the desired Access type if needed.

ADDING PRODUCTS TO YOUR GMC ACCOUNT

What is a Primary feed or data source?

A Primary feed or primary data source is how we upload your product data to Merchant Center. It is currently the only way products can be added and removed.

There are currently different ways to do this:

• Adding individual products by manually entering them through Merchant Center
• Adding products in bulk via CMS integration using the API or plugins (ex. Shopify, Wordpress, Wix)
• Adding products in bulk via a Third-party App (ex. DataFeedWatch)
• Adding products in bulk via a live Google Sheets spreadsheet upload
• Adding products in bulk via a file upload (You can use .txt, .xml, or a .tsv.)
• Products are automatically added when found by Google

These Primary feeds have required attributes that need to be included because this basic product information serves as the foundation for creating successful free listings and ads for your products.

A sample basic Primary feed with only the required attributes could look like:

Find the complete list of required and optional feed attributes with this Product data specification article.

Adding products via CMS (Shopify, Wordpress, Wix)

How To Add Products via Shopify

In order to add products to Merchant Center using Shopify (via the Shopify API), follow these steps:

• Go to your Shopify admin

• Select Channels > Add Sale Channel > select Google & YouTube

• Click Connect Google Account and enter the same Google Account you use to manage all your Google properties (ie. Google Business Profile, Google Analytics, Google Ads, etc.)

• Review the setup requirements for your online store and make any required changes.

• Select a Merchant Account from the drop-down list (note: the Merchant Center IDs listed are the IDs associated with your Google account where your Google account is an administrator) or create a Merchant Center account by clicking Create new and then create an account from Google Merchant Center.

• Verify yourself as the account owner.
• In the Verify it's you section, enter your phone number, select your country from the drop-down menu, and then click Get code to receive your verification code.
• In the Verify it's you dialog, enter the 6-digit code that you receive by text message to your phone.
• Click Verify.

• Click Select beside Target market to set up where you want to sell your products, and then select a target market and the language. Your store's currency settings determine the countries and regions available for you to target. The languages available are based on those supported by Google, and depend on your target market.

• Click Select beside Shipping settings, and then click the drop-down menu to select automatic if you want to automatically import your shipping settings to sync your shipping rates from Shopify, or manual if you manually want to set up your shipping settings within Merchant Center and configure your shipping rates. Then hit Save.

After you complete setup, products that are available to your online store automatically sync with Google. For eligible stores, products synced to Google Merchant Center using the Google & YouTube channel can be displayed on relevant Google surfaces for free.

How To Add Products via Wordpress

[WATCH THIS SPACE]

How To Add Products via Wix

[WATCH THIS SPACE]

Adding products via Third-party App (DataFeedWatch)

Adding and managing your products via a third-party app such as DataFeedWatch has many benefits for producing optimised Merchant Listings, especially when it comes to large product data sets.

DataFeedWatch allows us to set up the required foundational as well as tailored rules required to match your product data set exported from your CMS (Shopify, Wordpress, Wix, etc.) to the required and additional optional fields available with Merchant Center and generate different types of optimised and targeted Free Product Listings & Free Local Listings primary feeds, supplemental feeds, local inventory feeds, etc.

Products Found by Google

One of the standout features of Merchant Center Next compared to the Classic Merchant Center is its ability to automatically crawl your website to identify and add products (similar to how it handles promotions), even if these products haven’t been explicitly included in your submitted feed. These automatically discovered items appear under the Found by Google data source in Merchant Center.

For this feature to work, your website must have structured data markup (product schema) properly implemented on all product pages.

Should You Enable This Feature?

There are pros and cons to consider when deciding whether to keep this feature enabled.

• Recommended to Disable: If you or your agency has already optimised your product feeds to feature only the products you want to appear in Merchant Listings, we recommend disabling this feature. This approach ensures full control over which products are live, preventing unexpected or incomplete products from being displayed.
• When to Enable: If your product data within your CMS is consistently accurate, comprehensive, and well-maintained, and you prefer not to rely on a dedicated merchant feed management system, enabling this feature could streamline product additions. However, this requires confidence in the quality of your behind-the-scenes product data.

By carefully weighing these considerations, you can decide whether this automated feature aligns with your business needs and operational workflows.

Understanding Your Feed Settings

Your feeds will have a number of set up rules and settings to determine information about the data source and how it will be used.

About the data source:

• SCHEDULED UPDATES – tells GMC when you would like for it to automatically check for updates. We usually recommend every 24 hours at 12 AM.

• FILE URL – this is the link to the merchant feed you have uploaded

• CREDENTIALS – saved usernames and passwords that are used to access the data source (optional)

• SOURCE NAME – this is the name of your feed or data source. We recommend giving this a unique name that will enable you to easily distinguish between other feeds you will upload in the future.

How the data will be used:

• COUNTRIES – what countries you want the mechant listings generated by the data source to appear in

• LANGUAGE – the set language of the data source

• MARKETING METHODS – (previously known as Destinations), Marketing Methods determine how and where your products are displayed to potential customers on Google. Once your product data is uploaded to Merchant Center, these methods allow you to control whether your products appear across various Google surfaces (such as Search, Shopping, or Display) or are shared with other Google platforms.

• FEED LABEL – a name that helps categorise and identify the products in ads campaigns.

Creating Feed LabelsWhen creating a new product data source in Merchant Center Next, you must specify the country, language, marketing methods, and feed label. However, once the product data source is created, the language and feed label cannot be changed.

Key Differences in Feed Labels: Classic Merchant Center vs. Merchant Center Next

In the Classic Merchant Center, a single product data source could support multiple label and language combinations (referred to as "data targets"). In contrast, Merchant Center Next limits each product data source to a single data target, meaning one unique combination of feed label and language.

If a product data source previously included multiple feed label-language combinations, it will now be reorganised into multiple distinct product data sources, each with its own unique feed label and language pairing.

Modifying Feed Labels

If you need to change a feed label, the only option is to delete the existing product data source and create a new one with the desired label.

• USAGE OF PRODUCT DATA FROM THIS DATA SOURCE – determine where your products and store information will be shown   Online stores only: shows your products and store information to people shopping online

Local and Online stores: shoes your products and store information to people nearby using local inventory ads and free local listings as well as to online shoppers via shopping ads and free listings

OPTIMISING YOUR ACCOUNT SET UP

Connecting your Google Properties (GA4, Business Profile, Search Console)

Linking your Google Property accounts allows you to access specific conversion details, reporting and insights in Merchant Center.

Google Analytics

To link your accounts, you need to have editor access to your Google Analytics property and admin access to your Merchant Center account.

• Within GA4, navigate to the Admin gear icon on the lower left corner of your dashboard. Scroll down to the Product links section and click Merchant Center links.

• Select Link then Choose accounts. This will give you a list of the Merchant Center accounts you have admin access to and select the GMC account you wish to link. Then hit Next.

• Within Configure settings, ensure to enable Auto-tagging.

• Review then submit!

Google Search Console

You must first ensure you have added your website property to Google Search Console and have properly verified your site ownership via Domain or Property to give you access.

• Navigate to the left-hand side of your Search Console dashboard and select Shopping tab listings.

• Click Associate Account. Once this is done, you should be able to see the below on your screen.

Google Business Profile

To connect your Google Business Profile to your Merchant Center account and add your stores:

• Login to your Google Merchant Center account and navigate to the Settings icon then select Apps and services.

• Under the Google Services section, click Add service and select Google Business Profile then hit Next.

• Select the Google Business Profiles you want to connect then click Next.

• Confirm the Business Profile then click Link.

Read more information on how to link a Business Profile you don’t manage.

Conversion Settings

Merchant Center conversion settings include Auto-tagging and Conversion annotations.

Auto-tagging

This feature adds the ?srsltid parameter to URLs that users click through to your site. This helps Google track conversions.

For example, if someone clicks on the Google search result for www.example.com, the final URL will look like www.example.com/?srsltid=123xyz.

To enable this, follow these steps:

• Navigate to your Merchant Center Settings icon and select Conversion settings.

• Toggle to enable Auto-tagging.

Conversion Annotations

This feature provides social proof to your shoppers by using your conversion data to display annotations such as “best selling” or “1k shopped in the past month” within your merchant listings to help you stand out.

This may be especially useful for merchants who are not eligible for product ratings or store ratings to be displayed to show positive customer interactions to build trust with potential shoppers.

Note: Conversion annotation is a beta feature and is still being tested. Beta features may not be eligible to show on Google, can change at any time, and may never be fully launched.

To enable this, follow these steps:

• Navigate to your Merchant Center Settings icon and select Conversion settings.

• Toggle to enable Conversion Annotations..

Your Business: Business Info

Once you’ve set up your Google Merchant Center account, it’s crucial that you input accurate business information settings. This step is essential before C9 can optimise your merchant listings and account settings, as verification is a prerequisite. This also impacts how your store will be displayed within Google Shopping. None of your merchant listings can go live unless this has been completed.

Your Business: Shipping and Returns

Including accurate and complete Shipping and Returns information is essential for your merchant feeds to be approved and your products to appear on Google Shopping. Without this information, your feeds will be disapproved, and your products won’t be eligible to display in Google Shopping features including ads and free listings.

Google requires this information to ensure transparency for shoppers. It’s also a key factor in assessing your overall Store Quality and Shopping Experience Scorecard, which influences how Google ranks your against competitors. Clear and reliable shipping and returns policies can improve your store's standing and appeal to customers, encouraging conversions.

By meeting these requirements, you not only comply with Google’s standards but also position your store as a trustworthy and customer-friendly option.

How to Add Your Shipping Policy

• Navigate to the left-hand side of your Merchant Center dashboard and select Shipping and returns.

• Select Add shipping policy.

How to Add Your Returns Policy

How to Sync Your Shopify Shipping Settings to GMC

ADVANCED FEEDS AND ADD-ONS

Supplemental feeds: Advanced data source management

Supplemental feeds are a secondary source of data that we can use to optimise listings in bulk. It doesn’t replace the primary feed but it’s used to provide more information or update existing details, such as the titles, product attributes and advanced fields (custom attributes) that may be missing or need to be improved from the primary feed.

When creating a supplemental feed, you’ll need to have the id attribute because this is what will be used to connect it to your primary feed so we can integrate the additional attributes into your feed, therefore, your merchant listings.

For example:

PRIMARY FEED SAMPLE

SUPPLEMENTAL FEED SAMPLE

As a result, the product with id 0123 will have the following attributes in its final merchant listing:

Title: Calibre9 Blue Printed Tee - Size M

Description: The Calibre9 Blue Printed Tee combines a sleek, modern fit with a vibrant blue print, perfect for adding a pop of colour to any look.

Link: https://calibrenine.com.au/products/blue-printed-tee/?variant=mediumImage Link: https://calibrenine.com.au/wp-content/uploads/blue-printed-tee.jpg

Additional Image Link: https://calibrenine.com.au/wp-content/uploads/blue-printed-tee-image-2.jpg

Price: $20 AUD

Availability: In stock

Brand: Calibre9

MPN: CA12345LIBRE9

GTIN: 49123456

Google Product Category: Apparel & Accessories > Clothing > Shirts & Tops

Condition: New

Age Group: Adult

Color: Blue

Pattern: Printed

Material: Cotton/Polyester

Gender: Unisex

Size: Medium

Free Local Listings

Free Local Listings are a type of Google Merchant Add-on (or program) that allows you to showcase your product offerings and shop information to local shoppers nearby on Google. If this has been successfully set up, you can expect to see merchant listings appear with Google Business listings, map packs, as well as product grids with a “Nearby” tag or location distance tag such as “3.0km away”. See examples here.

This is beneficial especially for merchants who have physical store locations so that you can show your in-store availability for users who are searching nearby.

How To Enable Free Local Listings:

• Navigate to your Settings (gear icon) and select Add-ons
• Within the Discover tab, look for Free Local Listings then click Add

Free Local Listings: Local Products Feed, Local Inventory Feed, Google Business Shops

To successfully be running Free Local Listings, it requires 3 main things–your Local Products Feed, Local Inventory Feed, and your Google Business Profile integration.

NOTE: If you have only added in the Shops without connecting a local inventory feed, your listings will still appear within your Google Business listing, but this will not accurately reflect the product availability in-store. All Shops will reflect the same product catalog because they’re based on online availability. This is not ideal for user experience, especially if your product offerings differ by store (for example, some product lines only available in certain locations). In such cases, it would be highly recommended to include a local inventory feed.

Google Customer Reviews vs. Product Ratings (+ Supported Reviews Partners)

Promotions

Automated Discounts

OPTIMISING YOUR STORE QUALITY

Your Business: Store Quality

Shopping Experience Scorecard

Shop / Store / Seller Rating

Top Quality Store Badge

ACCOUNT-LEVEL ISSUES

Warnings vs. Suspensions

Resolving account-level issues

PRODUCT-LEVEL ISSUES

Warnings vs. Disapprovals

Common Issues and Best Practices To Avoid Them

Addressing Product Issues in Bulk

OPTIMISING YOUR MERCHANT LISTINGS

The Calibre9 Method

The Calibre9 Method to optimising Merchant Listings is broken down into 3 initial phases:

Phase 1: RESEARCH

In this foundational phase, we conduct thorough analysis and research to set the campaign strategy:

GMC Audit

• Perform a comprehensive audit of your Google Merchant Center account(s) to assess its current state.
• Identify issues affecting performance, missed opportunities for improvement, and factors influencing listing quality.
• Review your website’s product page backend to diagnose errors, incomplete fields, or gaps that could enhance your competitive edge.

Shopping Scraper Keyword Research

• Conduct campaign-specific keyword research, separate from standard SEO keyword research.
• Analyse trends in user search queries to uncover valuable keyword attributes for your GMC listings.
• Coordinate findings with Shopping Grids Research to inform Phase 3 mapping strategies.

Shopping Grids Research

• Investigate competitor Merchant Listings and Shopping Grid trends in the Shopping tab and Popular Products Grid.
• Identify filter criteria, subcategories, and recurring high-ranking products to understand why certain listings dominate visibility.

Outcome:

By the end of Phase 1, we’ll establish a tailored strategy for your GMC campaign and define the Schedule of Works.

Phase 2: FIXES

This phase addresses account and feed hygiene issues to lay a solid foundation for optimisation:

Set-Up & Tracking

• Ensure your Merchant Center account is correctly configured, including required fields and beneficial additional details.
• Integrate and enable tracking tools, such as Google Analytics, Search Console, and Business Profile.

Account Requirements & Fixes

• Resolve critical account-level and policy issues causing store suspensions or preventing listings from going live.
• Verify and complete all essential account settings.

Product Feed Requirements & Fixes

• Address product-level issues leading to listing disapprovals or limited visibility.
• Ensure all desired products are approved and live on Google.

Outcome:

All account and feed issues are resolved, and products are live, allowing us to move to Phase 3.

Phase 3: MAPPING & OPTIMISATION

With a clean foundation, we focus on optimising your Merchant Listings and product data for Google:

Program Add-Ons

• Enable and manage features like Store Ratings, Top Quality Store Badge, Customer Reviews, and more to enhance visibility and trustworthiness.

Additional Account & Feed Opportunities

• Activate and manage supplementary feeds and programs, such as local product feeds, promotions, loyalty programs, and payment options, to gain a competitive edge.

Product Page Fields Mapping

• Bulk-optimise missing or incomplete fields on product pages.
• Align product information consistently across backend data, schemas, and Merchant Listings to improve display and filtering.

Merchant Feed Mapping

• Use DataFeedWatch to map internal fields, establish channel-specific rules, and generate optimised primary and supplemental feeds.

Outcome:

You’ll achieve optimised Merchant Listings with enhanced product data and additional features, increased visibility, and access to additional Google surfaces and features.

SETTING UP YOUR PRODUCT PAGES FOR SUCCESS

Required Fields to Complete

Google is increasingly refining search results to resemble a category page experience, which highlights the growing importance of optimising product pages for eCommerce SEO. With ongoing updates to Merchant Center—and more anticipated—Google is pushing to ensure that product information is consistently aligned across product page data, schemas, and merchant listing data feeds.

Ensuring these elements are properly filled out allows Google to better filter and display your products in search results (both SERPs and the Shopping tab). The more detailed and accurate the product information, the better Google can leverage features like Popular Product Grids, Product Knowledge Panels, Compare Stores, People Also Buy From, and others to showcase your offerings.

This will be especially useful for the Product Page and Feed Mapping tasks of your Merchant Center campaign process. This will help us set up your feed rules within your DataFeedWatch for success, producing and future-proofing optimised listings for your products considering the following fields are filled out within your Shopify product settings.

In addition to the product information already commonly provided within product pages such as Titles, Descriptions, Tags, and Product Metafields, we recommend completing the following fields within the Shopify Product settings to facilitate a smoother integration with Merchant Center and to support effective data extraction for optimisation and automatic feed mapping:

MPNs & GTINs – *REQUIRED TOP PRIORITY*

When integrating your Shopify store with Google Merchant Center, accurately submitting the Manufacturer Part Number (MPN) and GTIN (Global Trade Item Number) is crucial. Google uses the MPNs to uniquely identify a specific product among all products from the same manufacturer and GTINs to identify the specific product/product variant that is sold by different retailers.

This affects your brand’s ability to be displayed as a retailer within shared product knowledge panels.

• MPN (Manufacturer Part Number): This is the manufacturer's unique code for a product. It is often the same as the product SKU (Stock Keeping Unit).
• GTIN (Global Trade Item Number): This is the product’s unique identifier, commonly found as the barcode.

View: Shopify Product Settings

Many issues in Google Merchant Center arise from incorrect or incomplete GTIN or MPN entries on Shopify causing the products to be either disapproved or be given limited visibility.

To avoid errors, ensure that:

• The MPN is accurately filled out.
• The GTIN (barcode) is provided correctly.

View: Shopify Product Settings

By properly managing these attributes, you can improve the accuracy of your data retrieval for your product listings and enhance your store's performance in Google Merchant Center.

View: Merchant Center Product Settings

Advanced Google Fields

We also recommend filling out the following default Google Variant Metafields where applicable and choosing from the provided acceptable options from Google below:

• Age Group (options: adult, infant, kids, newborn, toddler)
• Condition (options: new, refurbished, used)
• Gender (options: female, male, unisex)
• Size Type (options: big, maternity, petite, plus, regular, tall)
• Size System (ex. “AU”, “US”, “EU”, “UK” – important to note which one especially if you have varying size systems for shoes vs. clothes, etc.)

View: Shopify Product Settings

Google Product Category Metafields

The Google product category attribute (Google product taxonomy) is used to categorise your products to improve the targeting and delivery of your Merchant listings.

We recommend selecting the relevant categories for your product. Once you have selected this, you will be able to complete the Category Metafields for each. This affects the way your product details are displayed within the Product Knowledge Panels.

It’s important to note that these meta fields vary depending on the selected category.

For example, a moisturiser product would be classified under Lotions & Moisturizers in Skin Care and the Category Metafields would be as follows:

This would be different to for example, a boat propeller which would be classified under Boating & Water Sports in Outdoor Recreation whose Category Metafields would be as follows: