ISR · Incremental static regeneration
ISR (Incremental Static Regeneration) is the periodic regeneration of static pages, specific to Next.js. It is a compromise between content freshness and delivery performance: the page is served from a cache and rebuilt in the background.
Standalone definition · 36 words
How does ISR work?
A page is generated at build time or on the first request, then served as a static file. After a set revalidation delay or on demand, Next.js regenerates it in the background and replaces the cached version. Visitors get complete HTML immediately.
Why is ISR good for SEO and GEO?
Complete HTML is present in the initial response, which serves crawlers without JavaScript rendering. TTFB stays low thanks to the cache or CDN. You do need to watch freshness: a revalidation delay that is too long can serve a stale price or stock to bots.
ISR, SSR or SSG?
SSG generates at build time, ISR regenerates at intervals or on demand, SSR generates on every request. ISR suits content that changes but not every second: product pages, articles, categories. Highly volatile data justifies SSR.
Frequently asked questions
Does ISR exist outside Next.js?
The term is specific to Next.js. Other frameworks offer equivalent mechanisms under other names.
How do I force an update?
With on-demand revalidation from a webhook or a CMS action.
Does ISR change anything for Googlebot?
Googlebot receives complete HTML. Check that cached content stays consistent with the visible version.
Related terms
Further reading
- Checklist GEO and LLM / AI 2026
- 2026 GEO Tools Comparison: The Decision Guide
- ← Back to the GEO glossary (114 terms)