Two of your pages, one query, split impressions.
Prism reads your own Search Console data and lists the queries where more than one of your pages is taking a real share of the impressions, with the share each page holds and the best-positioned one named as the page to consolidate into.
A threshold, not a hunch.
Most cannibalization lists are long because every query where two URLs have ever been returned lands on them. Prism sets a bar, states it on the page, and reports what clears it.
- A fifth of the impressions, each
- A page is a contender for a query when it holds at least 20% of that query's impressions in the window. One page on 95% and another on 5% is one page ranking, not two pages competing.
- Two contenders minimum
- A query is reported only when two or more pages clear that bar. Everything else stays off the list, so the list stays short enough to work through.
- Twenty impressions to be counted
- A page and query pair below 20 impressions in the window is ignored. Below that the share figure is arithmetic on noise.
- Ordered by what is at stake
- The list is sorted by the query's total impressions, so the query splitting the most demand is the first row, not the one with the most contenders.
The heatmap is the diagnosis.
Above the table, every contending page is a row and every contested query is a column, shaded by the share that page holds of that query. Two dark cells in one column is the picture of a split. A row that is dark across several columns is a page quietly competing with the rest of the site.
Open a row and you get each contender on its own, with its clicks, impressions, click-through rate and average position. Impression share alone cannot tell you which of two pages actually converts, and the page you consolidate into should be the one that does.
Different wording, same page.
The Cannibalization report groups by the exact query Search Console reported, because that is the unit Google served. The other half of the problem is two queries that mean the same thing, and that lives one report over.
- Nearest queries by meaning
- Open any query in Keywords and its Analysis page lists the queries closest to it in meaning, computed from stored query embeddings rather than from shared words.
- The ones sharing a page
- A neighbour that shares a ranking page with the query you opened is flagged. That overlap is the signal; similarity on its own is not.
- And the dated handovers
- The same page lists every URL that has ranked for the query and the dated moments one took over from another, which is often what a split turns into.
- of a query’s impressions makes a page a contender
- 20%
- of a query’s impressions makes a page a contender
- contenders before a query is reported at all
- 2
- contenders before a query is reported at all
- of history to look back over, and it keeps growing
- 16mo
- of history to look back over, and it keeps growing
- credits used by the report
- 0
- credits used by the report
Frequently asked questions
When does Prism call a query cannibalised?
When at least two of your pages each hold a fifth or more of that query's impressions in the window you are looking at, counting only page and query pairs with at least 20 impressions. One page on 95% and another on 5% is not two pages competing, it is one page ranking, and reporting it as cannibalization would bury the queries where something is actually being split.
Does it match queries by meaning or by exact wording?
The Cannibalization report groups by the exact query string Search Console reported, because that is the unit Google served. Meaning-based matching lives one report over: open any query in Keywords and its Analysis page lists the queries nearest to it in meaning, flagging the ones that share a ranking page with it. Between them you get both the split you can prove and the near-duplicate you would otherwise miss.
Which page does it tell me to keep?
The best-positioned contender, by average position over the window. Prism names it rather than merging anything: the fix is yours to make, and it is usually a redirect, a rewrite or an internal link, not a button in a tool.
What does it cost to run?
Nothing. It reads the Search Console data Prism already stores for the property, so it uses no credits, on every plan including the free one.
Elsewhere in Prism
What a split usually turns out to be
- Striking distance keywords Consolidating a split query often lands it on page two rather than page one, where this report picks it up.
- Internal link analysis Two pages competing for a query usually have the internal links to match. The link graph says which one your site is actually pointing at.
- Search Performance Cannibalization is one of 17 reports over the same stored Search Console data.
More features
- Data warehousing Google serves a rolling 16 months and drops the rest. Prism syncs Search Console into its own store daily, re-pulls the days Google revises, and keeps all of them.
- Site crawling Prism crawls your site, scores each page with Lighthouse, and reads the X-Robots-Tag header and the robots meta. Compare any two crawls to see what a release changed.
- AI answer monitoring Prompts put to ChatGPT, Claude, Gemini and Perplexity on a schedule, the complete answer kept, so every report number traces back to the sentence it came from.
- Smart Campaigns Define a campaign by URL and query pattern plus dates, and Prism tracks the group as one thing. The indexed view rebases each campaign to 100 so big and small compare.
- Segments A saved query or URL group built from plain rules. Pick one in the toolbar and every Search Performance report stays scoped to it. Brand vs non-brand in one click.
- Striking distance keywords Queries averaging positions 11 to 20 with real impression volume, ranked by what page one would be worth against your own click-through curve. No industry CTR table, no purchased benchmark.
- Internal link analysis Your internal links as a graph: link equity per page, orphans, click depth, the anchor text you actually use, and pages that rank for the same query with no link between them.
Find out which pages are fighting each other.
Connect a property and the report is there on the first sync, over whatever history Google still holds. Cannibalization, defined.