Server-Side Rendering vs. Static Site Generation: Which Is Better for LCP?
When building or rebuilding a website with a modern framework, one of the earliest architectural decisions is how content gets rendered. That choice has a direct, often underestimated, effect on LCP.
Key takeaways:
- Static Site Generation (SSG) pre-builds HTML at build time, typically producing the fastest LCP
- Server-Side Rendering (SSR) generates HTML per request, offering fresher content at some latency cost
- The right choice depends on how frequently content changes and how personalized it needs to be
- Hybrid approaches (like Incremental Static Regeneration) offer a middle ground
- Neither approach fixes poor image or script practices on its own
The Core Difference
SSG builds every page's HTML in advance, during the build process, so serving a page is as simple as delivering a static file. SSR builds the HTML fresh for every request, which allows for real-time or personalized content but adds server processing time to each visit.
Side-by-Side Comparison
| Factor | Static Site Generation (SSG) | Server-Side Rendering (SSR) |
|---|---|---|
| Typical LCP performance | Fastest — no per-request processing | Fast, but slower than SSG due to server work per request |
| Content freshness | Fixed at build time (or periodic rebuild) | Always current, generated per request |
| Best for | Marketing pages, blogs, documentation | Personalized dashboards, frequently changing data |
| Server load | Minimal — serving pre-built files | Higher — rendering work happens on every request |
| Scaling considerations | Scales easily via CDN caching | Requires scalable server infrastructure |
When SSG Makes the Most Sense
For content that doesn't change per visitor — homepages, blog posts, product listing pages that update periodically rather than in real time — SSG is usually the better choice for LCP. Since the HTML is already built, there's no server-side rendering delay standing between the request and the response.
When SSR Is Worth the Trade-off
If content genuinely needs to be personalized or reflect real-time data — a logged-in dashboard, live inventory counts, or user-specific recommendations — SSR is often necessary despite the added per-request cost. The key is limiting SSR to the pages that truly require it, rather than applying it site-wide by default.
A Middle Ground: Incremental Static Regeneration
Some frameworks offer a hybrid approach that regenerates static pages periodically or on-demand, combining much of SSG's speed with content that doesn't go stale indefinitely. This can be a reasonable compromise for content that updates occasionally — like product pages with periodic price or stock changes — without needing full per-request rendering.
Frequently Asked Questions
Does SSG always produce a better LCP than SSR?
In most cases yes, since there's no server-side processing delay per request, but the gap narrows if SSR is well-optimized and running on fast infrastructure.
Can I mix SSG and SSR on the same site?
Yes — many modern frameworks support this, letting you use SSG for marketing and content pages while reserving SSR for pages that genuinely need per-request rendering.
Does client-side rendering (CSR) ever make sense for LCP-sensitive pages?
Generally not for public-facing content pages, since CSR tends to delay initial content the most. It's more appropriate for logged-in application interfaces where LCP matters less than overall interactivity.
Next Steps for Your Business
Review which pages on your site actually need real-time or personalized content, and consider whether those pages could move to static generation or a hybrid regeneration approach instead of full SSR.
Our development team can assess your current rendering architecture and recommend the right mix of SSG, SSR, or hybrid rendering for your specific content.