Comparison

A short, honest look at how isorouter differs from other client-side routers, so you can tell when it's the right fit — and when it isn't.

At a glance

Router	Frameworks	Built on	Type-safe paths	Data layer	SSR	Size
isorouter	Svelte · React · Vue (+ headless core)	Navigation API	✅ as const	❌ by design	❌ by design	~1.8 KB
react-router	React	History API	⚠️ via typegen	✅ loaders/actions	✅	Larger
TanStack Router	React · Solid	History API	✅ best-in-class	✅ loaders	✅	Larger
wouter	React · Preact	History API	❌	❌	⚠️ partial	Small (~2 KB)

Sizes are approximate

Only isorouter's ~1.8 KB gzip is a measured figure (Bundlephobia). The others drift across versions and configurations — check Bundlephobia for current numbers. "Larger" reflects the built-in data/SSR layers, not bloat.

What makes isorouter different

Two things no other router in the table does:

1. It's built on the Navigation API, not the History API. Click interception, history entries, scroll restoration and focus are the browser's job — isorouter orchestrates matching and commits on top instead of reimplementing the history stack. That's why the core stays ~1.8 KB.
2. It's framework-agnostic from one implementation. A single core publishes an immutable snapshot; thin adapters bridge it into Svelte, React and Vue (and you can use the core headless). The others are tied to one ecosystem.

Choose isorouter when

• You target modern browsers (or will ship a polyfill) and want to lean on the platform rather than re-implement it.
• You want a tiny, type-safe SPA router with zero runtime dependencies.
• You build for more than one framework, or want a framework-agnostic core you can wrap yourself.
• You don't need SSR or a built-in data-loading layer — you fetch in components or guards.

Consider something else when

• You need SSR/SSG. Reach for a meta-framework (SvelteKit, Next, Nuxt) — the Navigation API is a browser API and doesn't exist on the server.
• You want a built-in data-loading / caching layer. TanStack Router and react-router ship loaders, actions and revalidation; isorouter deliberately doesn't.
• You need typed, validated search params. That's TanStack Router's headline feature; isorouter hands you the raw URL and stays out of the way.
• You must support older browsers without shipping a polyfill. A History-API router works everywhere today; isorouter's reach follows Navigation API Baseline.

The honest limitation

isorouter's biggest trade-off is browser reach, not features. The Navigation API reached Baseline in early 2026 but is not yet Widely available — if a meaningful slice of your users are on older engines and you can't ship a polyfill, a History-API router is the safer choice today.

Next steps

• Browser support — the polyfill story in detail.
• Type-safe navigation — the headline TypeScript feature.
• FAQ — non-goals and design rationale.