What if building fast, dynamic websites didn’t require piles of JavaScript? What if traditional server-rendered pages could actually feel snappy and interactive?

Welcome to the showdown: HTMX vs. SPA. They both promise interactivity, but they go about it in very different ways. One loads JavaScript-heavy bundles. The other adds sprinkles of AJAX in the old-school HTML world.

Let’s break it down and rethink how performance and interactivity can work together. Buckle up!

💡 What is HTMX?

HTMX is a lightweight JavaScript library (just ~10KB!). It lets HTML do more than you’d expect. Instead of using big JavaScript frameworks, HTMX gives regular HTML elements the power to send AJAX requests, update parts of the page, or even push browser history states.

Think of it like this:

  • You click a button.
  • It sends a request to the server.
  • The server sends back a tiny chunk of HTML.
  • HTMX swaps that chunk into the page — no full reload, no rehydration, no heavy JS.

Cool, right?

💻 What is a SPA?

A Single Page Application (SPA) is a web app loaded as one big shell. Once you’ve opened it, it doesn’t fetch entire new pages—just data. Libraries like React, Angular, and Vue dominate this space.

SPAs offer really smooth user experiences. Navigation feels instant. They use JavaScript everywhere — to manage routing, handle UI, manage state, and talk to APIs.

But managing all this comes at a price.

🚀 Performance Showdown

This is where the sparks fly.

🏁 SPAs

  • Need to load lots of JavaScript up front.
  • Might cause a blank screen while loading (hello, loading spinners 👋).
  • Require client-side routing and rendering.
  • Harder to make SEO friendly.

⚡ HTMX

  • No heavy JS bundles.
  • Progressive enhancement — works even if JS fails.
  • Server renders HTML. The client just swaps it in.
  • Way easier to make accessible and SEO-ready.

Conclusion? HTMX usually wins on initial performance and simplicity — especially for content-rich websites that don’t need extra complex interactivity.

🧠 Developer Experience

Let’s talk about how it feels to build with these approaches.

HTMX:

  • You write mostly HTML and server-side code.
  • No need for state management libraries.
  • Can use your favorite server-side language — Python, Ruby, Go…
  • Back to basics. Clean and clear.

SPA frameworks:

  • You use components, often in JavaScript or TypeScript.
  • You need to manage state, maybe use Redux or Vuex.
  • You often split logic between frontend and backend.
  • Sometimes feels like building an entire app inside the browser.

HTMX keeps you focused. SPAs give you flexibility but demand more complexity. Choose your flavor!

🏗️ When Should You Use a SPA?

SPAs aren’t bad. They’re powerful. Use them when:

  • You’re building a full-blown app like Gmail or Trello.
  • You need real-time updates or complex client-side logic.
  • You want super slick transitions, animations, or drag-and-drop.
  • You don’t mind the complexity — or you’ve got a team to manage it.

SPAs are amazing when they make sense. But many projects don’t actually need them.

🌱 When Should You Use HTMX?

HTMX is ideal when you want to:

  • Serve content fast and improve Time-To-First-Byte (TTFB).
  • Keep your architecture simple — server-rendered, just enhanced with AJAX.
  • Build forms, dashboards, or admin panels quickly.
  • Focus on accessible, SEO-friendly websites.

It shines in content-driven sites, CRUD apps, and places where performance matters.

🌐 Real World Example

Let’s say you have a blog page. You want to let users load more posts without reloading the whole page.

With SPA:

  • You build a React component.
  • Connect it to an API endpoint.
  • Manage a loading state, use hooks, bind state to DOM, maybe add a spinner too.

With HTMX:

  • Add hx-get="/load-more-posts" to your “Load More” button.
  • Add hx-target="#post-list" to tell HTMX where to insert the new HTML.
  • Done.

All the logic stays server-side. No front-end components, state, or hydration to worry about.

🔄 Interactivity Doesn’t Have to Be So Hard

One big lesson from HTMX is: you can build interactive sites without turning everything into a full-blown app.

It’s not about choosing between boring static HTML and hyper-complex SPAs. HTMX lives in the middle ground.

You can even mix and match — build one part of your site as a SPA where needed, and use HTMX for the rest.

🎯 Final Thoughts

So, HTMX vs. SPA — who wins?

  • Want speed, simplicity, and server-awesome rendering? Go with HTMX.
  • Need rich client-side features and complex UI logic? Choose a SPA.

But don’t just follow the crowd. Choose the tool that fits your project — and keeps your team (and users!) happy.

Sometimes, less JavaScript is more fun. And faster, too.

The future of interactivity might just be HTML again — with little sprinkles of magic.