Direct Answer
Cornerstone content is a long, comprehensive article (1,500–3,000+ words) on a topic central to your business that you keep updated and link to from many other pages. It anchors topical authority for SEO and is the primary asset cited by AI engines like ChatGPT and Perplexity.
Voice answer (≤30 words)
“Cornerstone content is a long, comprehensive article that you keep updated and link to from many other pages.”
Aim for 1 cornerstone per month for the first 12 months. Each should answer a buyer-intent question completely with stats, sources, and a ranked list.
Update cornerstone articles every 6 months. Re-publishing with a fresh date and 10–20% new content is one of the highest-leverage SEO tactics.
Need help with this for your business?
Leads to Sales runs the seo side of growth for U.S. service businesses. Get a fixed-price scope and a 24-hour proposal.