Product Feed Rules and Attribute Mapping in Merchant Center

Feed rules are now called attribute rules in Merchant Center. They let you change how product data from your sources becomes the final value Google uses, without editing the source itself: map a column to the right attribute, combine values, clean up text, or pick the most recent value from several sources.

This guide covers where attribute rules live, the operations and modifications available, how conditions work, how to test rules before they go live, how rules cascade, and practical examples. It also covers when a rule is the wrong fix.

What attribute rules do

Google’s attribute rules documentation describes them as a way to set the final value of each product attribute from your data sources. Every attribute already has a default rule, which takes the value from the supplemental or primary source. You add rules to change that: transform the value, pull it from a different column, or apply it only to some products.

Rules are attached to a primary data source and run each time that source is processed, so they keep working on every upload rather than fixing data once.

When rules help

• Your file uses different column names or formats from Google’s specification.
• A platform app can’t send an attribute you need, but the information exists in another field.
• Text contains something Google doesn’t allow, such as promotional phrases in titles.
• Several sources supply the same attribute and you need to choose which one wins.

Before you start

• Enable the Advanced data source management add-on (Settings > Add-ons). Attribute rules require it.
• Know which primary source and feed label the rule should apply to; if a source has several feed labels, you select one.
• The id attribute is handled by separate ID rules, not attribute rules.
• Keep a short change log of each rule: what it does, why, and when you added it. Rules are easy to forget about.

How to create an attribute rule

1. Go to Data sources, open Product sources, and select the primary source.
2. Open the Attribute rules tab. If the source has several feed labels, select the one you want.
3. Click Add attribute rule and choose the attribute.
4. Choose a data source operation (where the value comes from).
5. Add any modifications (how the value is changed).
6. Add conditions if the rule should apply only to some products.
7. Save as draft.
8. Test rules and preview the draft value for individual items.
9. Apply changes, then reprocess the data source so the rule takes effect.

Google’s interface may change labels over time; the sequence of draft, test and apply is the part to keep.

Data source operations

A data source operation decides where the attribute’s value comes from. Google lists four. The descriptions below are plain-language summaries; use the draft preview to see exactly what each produces for your data.

Operation	In short	Typical use
Set to	Use a field from a source, or a fixed value	Map a custom column to a Google attribute
Set to multiple	Use more than one field or value	Attributes built from several inputs
Extract	Take part of a value	A value embedded in a longer text field
Take latest	Use the most recently updated value across sources	Price and availability from a faster supplemental source

Take latest is how Google replaces deprecated online inventory sources: a supplemental source with id, price and availability, linked with a Take latest rule. See supplemental feeds explained.

Modifications

After choosing the source of a value, you can modify it. Google lists these modifications (summarized in plain language):

Modification	What it does
Prepend	Adds text or another value before the current value
Append	Adds text or another value after the current value
Add repeated field	Adds another value to an attribute that accepts several
Optimize URL	A modification for URL values such as link
Find & Replace	Replaces matching text with something else
Calculate	Performs arithmetic on numeric values
Split & Choose	Splits a value by a separator and keeps the part you choose
Clear	Removes the value

You can chain several modifications in one rule. Test each step; a Find & Replace that looks harmless on one product can damage another.

Conditions

Conditions limit a rule to products that meet criteria, such as a certain brand or product type. Google notes some behaviors worth knowing before you write them:

• Combine conditions with AND or OR.
• Price conditions use numbers without the currency.
• “Equals” is an exact match: 13.00 is not equal to 13.
• Matching is case insensitive.

Testing and rule order

Test before applying

Saving a rule as a draft lets you preview the value it would produce for individual items. Check a sample that covers the edge cases: products with and without the field you’re using, variants, long titles, and anything in the condition’s boundary. Only then apply the changes.

Rules cascade

Rules for an attribute run in order, each working on the result of the one before. Order matters: a rule that appends the color to the title should run after the rule that cleans the title, not before.

Rules and other changes in Merchant Center

Attribute rules aren’t the only thing that changes final values. On the Needs attention tab, Merchant Center can offer automatic fixes that work as persistent rules, and suggested attribute values. Google notes that accepted suggestions override later changes from other methods such as file uploads; you can view or revert them in Product details > Edit product. If a value isn’t what your rule should produce, check whether one of these is overriding it.

Examples

Map a custom column to brand

Your export has a column called “manufacturer”. Add a rule on brand with Set to, choosing the manufacturer field. No condition needed.

Remove promotional text from titles

Google’s title rules don’t allow promotional text, prices or shipping information. If your titles end in “Free Shipping”, a Find & Replace on title replacing it with nothing removes it from the feed. Fix the product names on your site too if the phrase appears there. See product titles for Google Shopping.

Add the color to variant titles

Google asks you to distinguish variants in the title. For apparel where the title lacks the color, Append the color value to title with a separator, conditioned on products that have a color. See managing product variants.

Pick up faster price and stock updates

Set price and availability to Take latest across the primary and a supplemental source that you update more often.

Exclude a brand from Shopping ads

Set excluded_destination to Shopping_ads with a condition on brand. The products stay in the account and can still appear in free listings.

When a rule is the wrong fix

Rules change what Google receives. They don’t change your website, and Google checks your data against the website.

• Price and availability: Google compares these with the landing page and structured data. A rule that changes price (for example with Calculate) creates a mismatch unless the page shows the same value. See aligning website data and product feeds.
• Identifiers: don’t use rules to generate GTINs or copy them between products. Google says not to make up or guess identifiers.
• Root causes in the platform: if every product needs the same fix, fixing the platform export is usually more durable than a rule nobody remembers.

Rule mistakes can also disapprove products at scale. After applying a rule, check Products > Needs attention for new issues; using Merchant Center diagnostics explains how.

When to get help

Attribute rules are powerful and easy to get subtly wrong, especially when several sources and rules interact. If you’re inheriting an account full of old feed rules, or need rules that work across a large catalog, our product feed optimization service can review and rebuild them, and fix what belongs at the source.

Frequently asked questions

Sources

• Google Merchant Center Help — Set up your attribute rules
• Google Merchant Center Help — Create a product data source
• Google Merchant Center Help — Feed labels
• Google Merchant Center Help — The Needs attention tab
• Google Merchant Center Help — Title [title] and structured title
• Google Merchant Center Help — How to fix: Mismatched product price
• Google Merchant Center Help — Product data specification

Last reviewed October 10, 2026 against the official documentation listed above. Google changes Merchant Center features and policies regularly — always confirm details in your own account.