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    Field: id

    Duplicate Product IDs in Google Shopping Feed

    Multiple products in your feed share the same ID. Each product must have a unique identifier to be properly tracked and displayed.

    Use our free Feed Validator to check for this and other errors automatically.

    What This Error Means

    The id attribute in your feed must be unique for each product within a single Merchant Center account. When multiple products share the same ID, Google cannot distinguish between them, causing processing errors.

    Consequences of duplicate IDs include:

    • Only one product version will be processed; others are rejected
    • Product data may be overwritten unpredictably
    • Historical performance data becomes unreliable
    • Inventory and pricing updates apply to wrong products
    • Feed processing errors and rejections

    IDs should remain stable over time — don't change a product's ID unless it's a genuinely different product. Understanding feed management fundamentals is essential for long-term stability.

    How to Fix It

    1. Audit your feed for duplicates — Export your feed and check for any products sharing the same id value.
    2. Use SKUs or unique identifiers — Your product SKUs from your inventory system are usually good unique identifiers.
    3. Differentiate variants properly — Color/size variants should have unique IDs. Use parent SKU + variant suffix (e.g., "SKU123-RED-M").
    4. Check data sources — If you merge data from multiple sources, ensure no ID conflicts between them.
    5. Use item_group_id for variants — Group related variants using item_group_id while keeping individual id values unique.

    Examples

    Incorrect
    <!-- Two different products with the same ID: -->
<item>
  <g:id>PROD-001</g:id>
  <g:title>Red T-Shirt - Small</g:title>
</item>
<item>
  <g:id>PROD-001</g:id>  <!-- Duplicate! -->
  <g:title>Red T-Shirt - Large</g:title>
</item>
    Correct
    <!-- Each variant has a unique ID: -->
<item>
  <g:id>PROD-001-RED-S</g:id>
  <g:item_group_id>PROD-001</g:item_group_id>
  <g:title>Red T-Shirt - Small</g:title>
</item>
<item>
  <g:id>PROD-001-RED-L</g:id>
  <g:item_group_id>PROD-001</g:item_group_id>
  <g:title>Red T-Shirt - Large</g:title>
</item>

    Additional Tips

    • Keep IDs stable — don't change them unless it's a different product
    • Use alphanumeric characters, underscores, and hyphens only
    • Maximum ID length is 50 characters
    • IDs are case-sensitive — "ABC123" and "abc123" are different
    • Set up automated duplicate detection in your feed generation process
    • Document your ID schema to ensure consistency across your team

    Related Issues

    Missing IDInvalid GTINMissing GTINBrand Missing or Invalid

    Validate Your Feed Now

    Use our free Google Shopping Feed Validator to check for this and other common errors before uploading to Merchant Center.

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