Which products to categorize first when the catalog is too big to do at once

The order, and why

Do not categorise five thousand products in alphabetical order.

First: products with rules attached

For most products the category is optional. For a few kinds, Google says which category they may use:

• Gift cards: 53, Gift Cards & Certificates.
• Phones and tablets sold with a contract or instalments: 267 Mobile Phones, or 4745 Tablet Computers.
• Software sold by subscription: 313, Computer Software.
• Alcohol: 499676, Alcoholic Beverages, or one of its subcategories.

And for products with a subscription_cost, the category attribute must be present at all. Search your catalog for these first; they are usually few, and they are the ones where a mistake is a policy problem. The specific categories guide has each rule in full.

Second: anything Merchant Center has flagged

Open Needs attention in Merchant Center and filter for category issues. Google says invalid values will be rejected and may prevent products from appearing, so these products may be invisible right now. Replace each value with a real ID, or remove it: a missing category is not an error. The invalid category guide walks through it.

Third: where the money is

Export last year’s sales by product and sort by revenue. Check how few products make up most of it; in many catalogs it is a small share. Those products deserve a category chosen by a person, at the most specific level that is true.

The payoff is in Google Ads. Shopping campaigns can split product groups by category, so precise categories on your best sellers let you bid on them separately rather than lumping them in with everything under the same broad parent. The Google Ads guide explains how.

Fourth: categories that bring requirements

Some categories change which attributes are required. Google’s product data specification requires color, size, gender and age group for apparel targeted at Brazil, France, Germany, Japan, the UK and the US. If you sell clothing in those countries, confirm those products sit in apparel and carry the four attributes before moving on.

Last: the long tail, in one pass

The remaining products are many and individually low-stakes. Doing them one at a time is where categorisation projects stall. Do them together instead:

1. Export id and title for every remaining product.
2. Run the file through the Bulk Mapper, which returns a category ID and path per row and flags the uncertain ones. The first 10 rows preview free.
3. Review only the flagged rows by hand.
4. Import the IDs back, and keep the file as your backup.