Template Cannibalization Index

Template Cannibalization Index (TCI) is the share of queries where 2 or more URLs from the same template rank against each other. It matters because URL-by-URL cannibalization audits miss the real problem on large sites: the template is generating duplicate intent at scale.

What TCI actually measures

The formula is simple: queries with 2+ ranking sibling URLs from one template / total ranking queries for that template x 100. If a faceted navigation template has 1,000 ranking queries and 320 of them trigger multiple color, size, or sort variants, the TCI is 32%.

That is actionable. A 32% TCI on a PLP template usually points to weak canonical logic, indexable parameter combinations, or thin differentiation between sibling pages. On enterprise sites, this is where the waste lives.

How to calculate it in practice

Pull query and landing page data from Google Search Console for 90 days. Join each URL to a template ID from your CMS, URL pattern map, or a Screaming Frog custom extraction. Then group by template + query and count distinct ranking URLs.

• Data sources: GSC for queries and clicks, Screaming Frog for URL pattern extraction, Ahrefs or Semrush for supplemental keyword overlap checks.
• Useful segmentation: brand vs non-brand, country, device, and template subtype.
• Practical thresholds: under 15% is usually fine, 15-30% needs review, over 30% is a remediation queue.

Moz and Surfer SEO are less useful here. This is not a content scoring problem. It is a template and indexing problem.

What causes high TCI

• Indexable facets with near-identical product sets
• Tag and category archives targeting the same head term
• Pagination, sort, and parameter URLs leaking into the index
• Location or language variants with weak differentiation
• Programmatic pages built from the same copy blocks and internal links

The fix depends on intent. Sometimes it is canonicalization. Sometimes 301 consolidation. Sometimes noindex. Sometimes the pages should stay separate, but the copy, title logic, and internal linking need to make the intent split obvious.

Where people get this wrong

The common mistake is treating every overlap as bad. It is not. Temporary query sharing between adjacent templates is normal, especially during reindexing, migrations, or when Google is testing result diversity. Google's John Mueller has repeatedly said there is no formal “penalty” for cannibalization; Google simply chooses the URL it thinks best matches the query. That is the caveat. TCI is a diagnostic metric, not a Google metric.

Another limitation: GSC query data is sampled and truncated. On very large sites, long-tail overlap is underreported. So use TCI as a prioritization model, then validate with server logs, indexation checks, and live SERP reviews. If Ahrefs shows overlap but GSC does not, trust neither blindly. Check the actual ranking URLs.

Used properly, TCI helps you fix one template and recover performance across 500 or 5,000 pages. That is why advanced teams track it.