Complete Guide to Product Pairing on Heureka with Mergado#

Product pairing is one of the most important tasks for successful advertising on the Heureka comparison site. This process links your online store’s offer with a specific product card in Heureka’s catalog. If your products are not paired, they only appear in full-text search, which significantly reduces their visibility and chances of generating orders.

Why Is Proper Pairing Essential for Online stores?#

• Joint display with competitors – Paired products are displayed directly on the “main” product card alongside offers from other online stores, so customers see your products in one place compared with the rest. Not as a standalone, isolated offer.
• Higher search ranking – Product cards rank higher in search results than standalone unpaired offers.
• Bidding capability – Only paired products can fully participate in bidding (setting the cost per click) and compete for top positions among sellers.
• Trust and reviews – Paired products let customers use reviews, ratings, and comparisons with other products.
• Heureka Marketplace – Correct pairing is one of the conditions for activating the orange “Buy via Heureka” button.

What Are the Key Elements for Successful Pairing?#

For Heureka to correctly identify and classify your product, you need to focus on these three elements:

• CATEGORYTEXT
• PRODUCTNAME
• EAN

CATEGORYTEXT#

CATEGORYTEXT is an element that must contain the full path to the correct product category according to Heureka’s catalog (e.g., Heureka.cz | Electronics | Mobile Phones). It is important for assigning products from the feed to the correct categories in Heureka’s catalog. The pipe character "|" is used as the separator between category and subcategory levels.

This is a crucial element for proper product pairing. If Heureka cannot pair categories due to an incorrectly filled CATEGORYTEXT, it will not proceed to pair products into product cards, and the product will not be displayed on Heureka.

You need to provide the complete full path, ideally following Heureka’s category tree. In that case, Heureka will automatically pair the categories and proceed to pair products into product cards.

You can also use your own category names, but this will extend the pairing process and there is a risk that categories – and therefore products – will not be paired and your products will not be displayed on Heureka.

• Example of a correctly filled CATEGORYTEXT element (e.g., for a washing machine):

Heureka.cz | Large Appliances | Washers and Dryers | Washing Machines

• Example of an incorrectly filled CATEGORYTEXT element (e.g., for a washing machine):

Heureka.cz | Large Appliances | Washers and Dryers

How to Correctly Fill the CATEGORYTEXT Element in Mergado#

Mergado loads and updates Heureka’s category tree data daily and makes assigning the correct categories much easier. You can easily set the correct categories in bulk using the Rename categories in bulk rule.

This rule works reliably when your input categories are in the correct element that Mergado expects for the given format. Before setting up categories, always check where and in what form your categories actually exist in the input feed (for Custom Format, for example, verify that elements are correctly mapped).

In most cases, you can use Rename categories in bulk, which works with existing input categories and assigns them to Heureka’s tree. However, situations may arise where categories are missing from the input or are in a different element than Mergado expects for the given format.

For example, with a Google feed, Mergado normally looks for categories in the g:google_product_category element. However, some online store owners only have categories filled in the g:product_type element while g:google_product_category is empty. In that case, you need a different approach. For instance, use the Bulk rewriting by values rule, which lets you write categories from the incorrect input element directly into the CATEGORYTEXT element (Mergado will suggest possible categories from Heureka’s tree).

How to use the Rename categories in bulk rule to fill CATEGORYTEXT:

1. In the selected Heureka project, go to the Rules page and click New rule.
2. Select Rename categories in bulk as the rule type.
3. If you want to assign categories from Heureka’s tree for all products, choose All products in the queries. Alternatively, select or create a new product query for which you want to assign categories.
4. Assign the corresponding Heureka tree categories to your online store categories.

a. The easiest way is to use the Suggest categories function. Mergado will automatically fill your online store categories on the left side and assign the corresponding Heureka tree categories on the right. Then review Mergado’s suggestions and adjust as needed.

b. Another option is the Pre-fill left side function. Mergado fills in your online store categories on the left side. You then manually assign the corresponding Heureka tree categories on the right. Mergado will suggest suitable Heureka tree categories based on keywords you type.

c. You can also fill in and assign categories manually on both sides. Even in this case, Mergado will suggest categories (both yours and from Heureka’s tree) so you do not need to look them up elsewhere.

Tip! The order in which categories are listed in this rule matters. The rule applies rows from top to bottom. It is advisable to place more general categories at the top and specific ones at the bottom. You can adjust this order when creating the rule.

5. If you do not want to review all categories, you can use the Show only filter to display only problematic rows (Conflicting rows, Invalid output categories, or Values missing on input).
6. Enter a rule name and click Create.

PRODUCTNAME#

PRODUCTNAME is an element that must contain the exact product name, and for successful pairing, its value must match the name of the product card on Heureka. It is a mandatory element of the Heureka feed and is needed for proper product display.

This element is key for product pairing – that is, for assigning your products to the corresponding product cards on Heureka. For correct pairing, the PRODUCTNAME element must contain all mandatory information for the selected category (e.g., for clothing, the size must be included directly in the name).

Mandatory data for individual categories and examples of correct names can be found on Heureka’s website. For example, for the Men’s socks category, the mandatory data are Brand | Line | Color | Size. A correctly filled PRODUCTNAME would look like this: VoXX ponozky Setra dark gray 35-38

At the same time, this element must not contain excessive information unrelated to the product name, such as a gift with the product, warranty information, free shipping, and similar items. The maximum text length is limited to 200 characters, which you can automatically enforce by setting up the Truncate value rule.

You can edit the PRODUCTNAME element in Mergado using various rule types, such as: Rewrite, Bulk rewriting by values, Data file import, or manual changes.

If your products are already paired on Heureka and you then make changes to the PRODUCTNAME element, the products will be unpaired and must go through the pairing process again. The duration of this process depends on Heureka’s capabilities.

How to Correctly Fill the PRODUCTNAME Element in Mergado#

One of the most common issues with the PRODUCTNAME element is a missing manufacturer (brand) name or a missing parameter (e.g., size).

How to Add the Manufacturer Name to the PRODUCTNAME Element?#

The simplest way to add the manufacturer name to PRODUCTNAME is to use the automation that Mergado offers.

1. In the selected project, click the Automation tab.
2. Click the automation called Add producer to product title.
3. Fill in the Manufacturer element name – enter the element from your input feed that contains the manufacturer name (e.g., MANUFACTURER).
4. Fill in the Product name element name – enter the element from your input feed that contains the product name (e.g., PRODUCTNAME).
5. As the Output product name element, enter PRODUCTNAME.
6. Click Run automation.

This creates a rule called “Add producer to product title.” Thanks to this rule, all products in the feed that are missing the manufacturer in their name will have the manufacturer name added to the PRODUCTNAME element. You can find the rule in the list on the Rules page, where you can also edit it.

How to Add Size or Another Parameter to the PRODUCTNAME Element?#

If you want to add another mandatory parameter for a given category (e.g., size, material, or whether it is men’s/women’s/children’s) to the PRODUCTNAME element, you need to create a rule in Mergado.

1. In the selected project, first create a product query on the Products page for the products where you want to add the selected parameter to PRODUCTNAME (e.g., for the Clothing category, you want to add the Size parameter to PRODUCTNAME, so you create a query containing all products from the Clothing category). See this guide on how to work with product queries.
2. Go to the Rules page and click New rule.
3. Select Rewrite as the rule type.
4. Choose the product query to which you want to apply this rule.
5. In the Element field, enter PRODUCTNAME (the element that will be modified by the rule).
6. In the New value field, enter all elements that should be included in the PRODUCTNAME element (including the original PRODUCTNAME if you want to keep it).

→ Since each product will have a different element value (each product has a different name/size/color), you need to mark these elements as variables. You do this by enclosing the element name with the "%" character at the beginning and end.

7. Enter a rule name and click Create.

Example:

Currently, the PRODUCTNAME element for a selected product contains “Nike t-shirt green.” You want PRODUCTNAME to read “Nike t-shirt green XL.” The size information is in the PARAM element, which contains nested elements PARAM_NAME (parameter name, e.g., size) and VAL (parameter value, e.g., XL).

In the New value field of the new rule, enter:

%PRODUCTNAME% %PARAM{PARAM_NAME="VELIKOST"} | VAL%

Mergado will understand that the new value of the PRODUCTNAME element should contain the original value (%PRODUCTNAME%, e.g., Nike t-shirt green) plus the information found in the element PARAM -> PARAM_NAME=“VELIKOST” -> VAL (e.g., XL).

You can add other parameters to PRODUCTNAME in a similar way, for example material. In that case, you would add %PARAM {PARAM_NAME=“MATERIAL”} | VAL% after the size, and Mergado would append, e.g., cotton after “Nike t-shirt green XL.”

It is important to remember that your feed must actually contain the values for the selected parameters. Otherwise, Mergado will have nothing to draw from and will not add anything to PRODUCTNAME.

You also need to make sure you always fill in the path to the parameter value (Element-Path) correctly so Mergado knows how to reach it. The path notation may differ from the example above if the elements with parameters in your feed have different names. But as soon as you type the initial % variable marker, auto-suggestions will appear, and you can simply select from the list.

EAN#

EAN contains a numeric code that identifies individual products. These are official barcodes, and Heureka supports the EAN-13 format, which consists of thirteen digits.

EAN is mandatory for the categories Books, Textbooks, Maps and Guides, Movies, Music, and Comics. For other categories, it is not mandatory, but it is recommended for all products, as it can significantly speed up pairing, helps automated processes, and is essential for generating the Unpaired products report.

Although Heureka does not pair products into product cards based on EAN codes, its Unpaired products report – which Heureka generates and where you can find information about unpaired products – works specifically with EAN codes. If you send EANs to Heureka, it will look up unpaired products by EAN and recommend the correct name and category for pairing in the report.

The unpaired products report is available in Heureka’s administration for your shop. It is available only for online stores in PPC mode, and Heureka generates it once a day.

How to Check EAN Correctness in Mergado#

How to Find Products with Invalid EAN in Your Feed?#

You can easily find products with invalid EAN using the Find products with invalid EAN automation.

1. In the selected project, click the Automation tab.
2. Click the automation called Find products with invalid EAN.
3. The automation has EAN pre-set as the EAN code element. Leave it as is.
4. Click Run automation.

The automation will save products with invalid EAN into a query called “Products with invalid EAN.” You can then fix the codes or temporarily hide these products (using the Hide product rule) until you fix the EANs.

How to Find Products with Missing EAN in Your Feed?#

You can find products with missing EAN by creating a query for them.

1. On the Products page, select the Simple interface option in the table.
2. For Search products, choose on input.
3. In the search field, type EAN and then choose the is empty option.
4. Click Search.
5. All products with a missing EAN will be displayed.
6. Enter a query name (e.g., Products with missing EAN).
7. Click Save.

On the same page, click the Saved queries tab to find this query. Ideally, try to fill in the EAN for these products as soon as possible, for example using the Data file import rule.

Advanced Automation with the Pairing Bear Extension#

If you have correctly filled EAN codes in your feed and do not want to waste time manually pairing products and reviewing the unpaired products report, you can use the Pairing Bear extension. It automatically pairs your products with product cards on Heureka based on EANs, and for items that cannot be paired, it offers intelligent recommendations, such as adjusting the name or category.

Regular Checks with Mergado Audit#

Regularly checking your feed with Mergado Audit helps identify errors that directly affect product pairing into product cards on Heureka. The audit lets you continuously monitor these issues, catch feed changes in time, and systematically increase the share of paired products and their performance.

More information about Mergado Audit can be found in the article Mergado Audit: Guide to Technical Product Feed Checks.

What Does Mergado Audit Check for Pairing-Related Elements?#

CATEGORYTEXT#

• Whether the CATEGORYTEXT element is missing or empty for products.
• Whether products have multiple CATEGORYTEXT elements. Heureka only processes the first occurrence of CATEGORYTEXT for each item.
• Flags when CATEGORYTEXT contains an invalid category level separator or extra separators.
• Whether the CATEGORYTEXT element contains only a single value (one level) of category, or whether this element contains an invalid value.
• Detects when CATEGORYTEXT contains links (URLs), which do not belong in this element.

PRODUCTNAME#

• Whether the PRODUCTNAME element is missing or empty for products.
• Whether PRODUCTNAME is duplicated – it should be unique for each product in the feed.
• Whether the PRODUCTNAME element has the correct length (maximum 200 characters).
• Detects when PRODUCTNAME contains prohibited words, links, or characters. For example, information about gifts or shipping does not belong in this element, nor do copyright, trademark, or similar symbols.

EAN#

• Whether EAN is missing or empty for products.
• Whether EAN codes are unique and there are no duplicate values (the same EAN for multiple products) in the feed.
• Whether the EAN element contains prohibited values, such as letters, spaces, hyphens, etc., instead of a numeric code.
• Whether the EAN element has the correct length.

Summary#

Correctly filled CATEGORYTEXT, PRODUCTNAME, and EAN elements form the foundation for successful product pairing into product cards on Heureka. If these data are accurate, complete, and meet Heureka’s requirements, it significantly increases the chance of correct pairing, better visibility, and effective bidding.

However, keep in mind that pairing is just one part of successful advertising. Heureka has additional requirements for feed structure and quality, and meeting them is essential to prevent products from being rejected and campaigns from being restricted. We cover this topic in more detail in the article Data Optimization for Heureka: How to Fix Errors in Your Product Feed and Ensure Heureka Does Not Reject Products.

FAQ#

What is product pairing on Heureka and why is it so important?#

Product pairing is the process of linking your online store’s offer with a specific product card in Heureka’s catalog. Paired products rank higher in search results, can use reviews and price comparisons, and enable full bidding. Without pairing, products only appear in full-text search, which significantly reduces their visibility and sales potential.

What advantages does correct product pairing bring to an online store?#

Correctly paired products have better positions in search results and allow you to set the cost per click. Customers also see reviews, ratings, and comparisons with competitors, which increases the trustworthiness of your offer. Pairing is also one of the conditions for activating Heureka Marketplace and the “Buy via Heureka” button.

Which elements are key for successful product pairing?#

Three feed elements play a crucial role: CATEGORYTEXT, PRODUCTNAME, and EAN. Each serves a different function – CATEGORYTEXT determines the category, PRODUCTNAME identifies the specific product. An important but not universally mandatory element is EAN, which helps with finding and checking unpaired items. If any of these elements is missing or incorrectly filled, pairing may fail.

How should the CATEGORYTEXT element be correctly filled?#

CATEGORYTEXT must contain the complete path to the category according to Heureka’s category tree. Individual categories and subcategories must be separated by the pipe character “|”. It is important to include all category levels; otherwise, Heureka may not classify the product correctly. An incorrectly or incompletely filled CATEGORYTEXT can halt the entire pairing process.

How can I set the correct categories for Heureka in Mergado?#

In Mergado, you can use the Rename categories in bulk rule, which lets you assign online store categories to categories from Heureka’s tree. Functions like “Suggest categories” or “Pre-fill left side” can significantly speed up the process. It is also important to order rules correctly – from general categories to specific ones.

What must the PRODUCTNAME element contain for correct pairing?#

PRODUCTNAME must match the product card name on Heureka and contain all mandatory data for the specific category, such as brand, color, or size. It must not include marketing information like free gift or free shipping. The maximum name length is 200 characters.

How do I add a missing brand to PRODUCTNAME in Mergado?#

In Mergado, you can use the “Add producer to product title” automation, which adds the manufacturer name from the appropriate element (e.g., MANUFACTURER) to PRODUCTNAME. The automation creates a rule that ensures the adjustment is applied to all relevant products, improving the chances of correct pairing.

How do I add size or another parameter to the product name?#

You need to create a Rewrite rule and use variables marked with the % character. Insert the original name into the new PRODUCTNAME value and add the path to the desired parameter (e.g., size from the PARAM element). It is essential to verify that the feed actually contains the needed values.

When is the EAN element mandatory and what is its significance?#

EAN is mandatory for the categories Books, Textbooks, Maps and Guides, Movies, Music, and Comics, but we recommend filling it in for other categories as well. Although Heureka does not pair directly by EAN, it uses it in the Unpaired products report. With EAN, Heureka can recommend the correct name or category for pairing.

How do I detect invalid or missing EAN codes in Mergado?#

For invalid EANs, use the “Find products with invalid EAN” automation, which creates a query of problematic items. Products with missing EAN can be found using simple search and a saved query. It is then advisable to fill in the EAN or temporarily hide the products.

What is Pairing Bear and how does it help with pairing?#

Pairing Bear is an extension that automatically pairs products based on EAN codes. For unpaired items, it offers intelligent recommendations for adjusting the name or category. This saves time and minimizes the need to manually review Heureka’s unpaired products report.

How does Mergado Audit help with product pairing checks?#

Mergado Audit checks the correctness of CATEGORYTEXT, PRODUCTNAME, and EAN elements and detects errors, duplicates, or invalid values. It flags, for example, empty names, invalid category separators, or incorrect text lengths.

Why is it not enough to just handle pairing, and why do I need to address other feed requirements?#

Pairing is just one part of successful Heureka advertising. The feed must also meet other technical and content requirements; otherwise, products may be rejected or campaigns restricted. That is why it is important to pay attention to overall data optimization and regular feed quality checks.