TypeScript is the default in new Next.js projects, and the framework is built with it. The payoff compounds on a team: types turn route params, page props and server data into compile-time contracts.
The App Router has specific typing patterns that differ from classic React apps — get them right and the whole codebase feels guided.
Typed dynamic routes
Dynamic route params are now asynchronous promises that you await. Type them explicitly and Next validates your route structure.
- params: Promise<{ slug: string }>.
- searchParams: Promise<{ [key: string]: string | string[] }>.
- Type your own data models once and reuse them across pages.
Types are documentation that cannot drift. A typed API client prevents a whole category of production bugs before they deploy.
Typed data fetching
Model your CMS and API responses as shared types, then import them in both server components and client components. Payload CMS generates these types from your collections automatically.
Typed forms and actions
Server Actions benefit from typed inputs and error handling. Keep action return types explicit so callers handle failures correctly.
Next.js + TypeScript FAQ
Is TypeScript required for Next.js?
No, but it is the default and strongly recommended. The framework ships types for everything, so the cost of opting in is minimal.
How do I handle untyped CMS data?
Most CMSs, including Payload, can generate types from your schema. For external APIs, define the contract yourself with interfaces.
