How to Use Custom Taxonomies for Product Categorization

When You Need a Custom Taxonomy

The default Google Product Taxonomy works for Google Shopping and general categorization. But many scenarios call for a different category structure:

• Marketplace requirements. Amazon, Otto, and eBay each have their own taxonomies that sellers must use.
• Internal category systems. Your ERP or PIM system likely uses its own category hierarchy that doesn't match Google's.
• Industry-specific taxonomies. UNSPSC, eCl@ss, ETIM, and other standards are used in B2B and specialized industries.
• Regional variants. Localized category trees for specific markets or languages.

Custom taxonomies let you match products against any of these structures.

File Format

Create a plain text file (.txt, UTF-8 encoded) with one category path per line. Use > to separate hierarchy levels:

Apparel & Accessories > Clothing > Shirts & Tops
Apparel & Accessories > Clothing > Pants
Apparel & Accessories > Shoes > Sneakers
Apparel & Accessories > Shoes > Boots
Home Goods > Kitchen > Cookware > Pots & Pans
Home Goods > Kitchen > Cookware > Baking
Home Goods > Kitchen > Small Appliances > Coffee Makers
Home Goods > Kitchen > Small Appliances > Blenders
Electronics > Audio > Headphones
Electronics > Audio > Speakers
Electronics > Computers > Laptops
Electronics > Computers > Desktops

A few format details:

• Hierarchy separator: Use > (with spaces). Level1 > Level2 > Level3.
• One path per line. Each line represents one complete category from root to leaf.
• UTF-8 encoding. Required for non-ASCII characters (umlauts, accents, etc.).
• ID prefixes are stripped. If your lines start with numeric IDs like 123 - Electronics > Audio, the system removes the prefix automatically.
• No header row. The file should contain only category paths, no column headers.

You don't need to include every possible path. Include only the leaf-level categories you want products matched to. The AI uses the hierarchy to understand the context, but it will match to the most specific category available.

How It Works

1. Go to the Matcher page.
2. In the Custom Taxonomy section, click "Choose File" and select your .txt file.
3. Upload your product data as usual (CSV paste or file upload).
4. Click Start Matching.

The AI reads each product's title and description and selects the best-matching category from your custom taxonomy. Results show the matched path from your taxonomy, not Google's.

Tips for Good Custom Taxonomies

Be specific enough. A taxonomy with only 10 broad categories ("Electronics", "Clothing", "Home") won't give useful results. Aim for at least 2-3 levels of hierarchy.

Be consistent with naming. Use the same terminology throughout. If you use "Shoes" in one branch, don't use "Footwear" in another unless they mean different things.

Include enough categories. If a product doesn't have a good match in your taxonomy, the AI will pick the closest option — which may be wrong. Make sure your taxonomy covers the product types you're categorizing.

Test with a small batch first. Upload 10-20 products and check the results before processing your full catalog. This lets you spot gaps or ambiguities in your taxonomy.

For detailed formatting specifications, see the Custom Taxonomy File Format Guide.