Free Keyword Cluster Tool
A pile of keywords isn't a content plan — clusters are. NToolHub's free Keyword Cluster Tool groups your text's significant terms by word stem into topic clusters, showing which themes dominate and which are thin. SEOs use it to plan pillar pages, H2 sections and supporting articles from existing content.
How to Use the Keyword Cluster Tool
- Paste an article, product copy or raw keyword list.
- Click Cluster Keywords to group related terms by word stem.
- Use the biggest clusters as H2 sections or supporting articles.
- Each cluster hints at a subtopic your content already covers — expand the thin ones.
Features
Paste any text or keyword list to get stem-based clusters ranked by frequency, each showing its top terms as tags — a visual topic map of your content with cluster sizes, all generated locally in your browser.
Benefits & Use Cases
Clustering turns raw keyword data into site architecture: strong clusters become H2 sections or pillar pages, thin clusters reveal expansion opportunities, and distinct clusters prevent keyword cannibalization across pages.
Tips
Treat each major cluster as one page or section (one intent per cluster), expand clusters with high frequency but shallow coverage, and merge clusters that are really the same topic phrased differently.
Frequently Asked Questions
What is keyword clustering?
Grouping related keywords by shared meaning or stem so each group (cluster) represents one topic — the basis for assigning one page per search intent.
How does the tool group keywords?
It normalizes words and groups them by shared word stems (first letters), ranking clusters by total frequency. It's a fast heuristic — refine edge cases manually.
How do clusters become content?
Each strong cluster maps to an H2 section, a supporting article, or a FAQ entry. Thin clusters are expansion opportunities for the next content sprint.
Can this prevent keyword cannibalization?
Yes — when two of your pages target terms in the same cluster, they're competing. Clustering makes those collisions visible so you can merge or differentiate.
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