Noindex for filters
Blocking unpopular filter combinations from indexing using meta robots noindex.
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What is noindex for filtersWhen to use noindexImplementationCanonical vs noindexCombined strategyDynamic logic (PHP example)In brief
Noindex for filters is a strategy for managing the indexing of URLs generated by filter applications on e‑commerce category pages. For combinations with low search demand (3+ filters, few products), the noindex directive is used to save crawl budget and avoid duplicate content.
What is noindex for filters
E‑commerce sites often generate thousands of filter URLs (price, size, brand). Most have no search demand. Using noindex on such pages preserves crawl budget for important pages.
When to use noindex
- No search demand (check in Google Keyword Planner / Yandex Wordstat)
- Combination of 3+ filters
- Few products in results (less than 5)
- Temporary filters (sales, seasonal products)
Implementation
HTML
<meta name="robots" content="noindex, follow" />
<!-- follow allows crawling links on the filter page -->Canonical vs noindex
- Canonical — when you want to consolidate the weight of several similar pages, and each may have some demand.
- Noindex — when you don’t want the page to appear in search results at all (no demand, low variation).
Combined strategy
- 1 filter (popular) → canonical to itself + index, follow
- 2 filters (medium demand) → canonical to itself (if demand exists) or to the category; index/noindex based on demand
- 3+ filters (low demand) → canonical to category; noindex, follow
Dynamic logic (PHP example)
PHP
$filterCount = count($_GET);
if ($filterCount >= 3) {
echo '<meta name="robots" content="noindex, follow">';
} elseif ($filterCount == 2 && !isPopular($filters)) {
echo '<meta name="robots" content="noindex, follow">';
} else {
echo '<meta name="robots" content="index, follow">';
}Always add a canonical to the main category for pages with noindex. This helps the search engine understand the preferred version.
FAQ
Common questions
No. Google stops considering pages with noindex, but internal follow links from those pages still pass link equity.
Analyse internal analytics (most used filters) and search statistics (queries containing filter names).
Set a 301 redirect to the main category or keep noindex but add a canonical to the main category.
Direct contacts
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