--- title: Route Segment Config description: Learn about how to configure options for Next.js route segments. url: "https://nextjs.org/docs/15/app/api-reference/file-conventions/route-segment-config" version: 15.5.15 lastUpdated: 2025-07-21 prerequisites: - "API Reference: /docs/15/app/api-reference" - "File-system conventions: /docs/15/app/api-reference/file-conventions" --- > The options outlined on this page are disabled if the [`cacheComponents`](/docs/app/api-reference/config/next-config-js/cacheComponents) flag is on, and will eventually be deprecated in the future. The Route Segment options allows you to configure the behavior of a [Page](/docs/app/api-reference/file-conventions/layout), [Layout](/docs/app/api-reference/file-conventions/layout), or [Route Handler](/docs/app/api-reference/file-conventions/route) by directly exporting the following variables: | Option | Type | Default | | --------------------------------------- | ------------------------------------------------------------------------------------------------------------------------- | -------------------------- | | [`experimental_ppr`](#experimental_ppr) | `boolean` | | [`dynamic`](#dynamic) | `'auto' \| 'force-dynamic' \| 'error' \| 'force-static'` | `'auto'` | | [`dynamicParams`](#dynamicparams) | `boolean` | `true` | | [`revalidate`](#revalidate) | `false \| 0 \| number` | `false` | | [`fetchCache`](#fetchcache) | `'auto' \| 'default-cache' \| 'only-cache' \| 'force-cache' \| 'force-no-store' \| 'default-no-store' \| 'only-no-store'` | `'auto'` | | [`runtime`](#runtime) | `'nodejs' \| 'edge'` | `'nodejs'` | | [`preferredRegion`](#preferredregion) | `'auto' \| 'global' \| 'home' \| string \| string[]` | `'auto'` | | [`maxDuration`](#maxduration) | `number` | Set by deployment platform | ## Options ### `experimental_ppr` Enable [Partial Prerendering (PPR)](/docs/app/getting-started/partial-prerendering) for a layout or page. ```tsx filename="layout.tsx | page.tsx " switcher export const experimental_ppr = true // true | false ``` ```jsx filename="layout.js | page.js " switcher export const experimental_ppr = true // true | false ``` ### `dynamic` Change the dynamic behavior of a layout or page to fully static or fully dynamic. ```tsx filename="layout.tsx | page.tsx | route.ts" switcher export const dynamic = 'auto' // 'auto' | 'force-dynamic' | 'error' | 'force-static' ``` ```js filename="layout.js | page.js | route.js" switcher export const dynamic = 'auto' // 'auto' | 'force-dynamic' | 'error' | 'force-static' ``` > **Good to know**: The new model in the `app` directory favors granular caching control at the `fetch` request level over the binary all-or-nothing model of `getServerSideProps` and `getStaticProps` at the page-level in the `pages` directory. The `dynamic` option is a way to opt back in to the previous model as a convenience and provides a simpler migration path. * **`'auto'`** (default): The default option to cache as much as possible without preventing any components from opting into dynamic behavior. * **`'force-dynamic'`**: Force [dynamic rendering](/docs/app/getting-started/partial-prerendering#dynamic-rendering), which will result in routes being rendered for each user at request time. This option is equivalent to: * Setting the option of every `fetch()` request in a layout or page to `{ cache: 'no-store', next: { revalidate: 0 } }`. * Setting the segment config to `export const fetchCache = 'force-no-store'` * **`'error'`**: Force static rendering and cache the data of a layout or page by causing an error if any components use [Dynamic APIs](/docs/app/getting-started/partial-prerendering#dynamic-rendering) or uncached data. This option is equivalent to: * `getStaticProps()` in the `pages` directory. * Setting the option of every `fetch()` request in a layout or page to `{ cache: 'force-cache' }`. * Setting the segment config to `fetchCache = 'only-cache'`. * **`'force-static'`**: Force static rendering and cache the data of a layout or page by forcing [`cookies`](/docs/app/api-reference/functions/cookies), [`headers()`](/docs/app/api-reference/functions/headers) and [`useSearchParams()`](/docs/app/api-reference/functions/use-search-params) to return empty values. It is possible to [`revalidate`](#revalidate), [`revalidatePath`](/docs/app/api-reference/functions/revalidatePath), or [`revalidateTag`](/docs/app/api-reference/functions/revalidateTag), in pages or layouts rendered with `force-static`. > **Good to know**: > > * Instructions on [how to migrate](/docs/app/guides/migrating/app-router-migration#step-6-migrating-data-fetching-methods) from `getServerSideProps` and `getStaticProps` to `dynamic: 'force-dynamic'` and `dynamic: 'error'` can be found in the [upgrade guide](/docs/app/guides/migrating/app-router-migration#step-6-migrating-data-fetching-methods). ### `dynamicParams` Control what happens when a dynamic segment is visited that was not generated with [generateStaticParams](/docs/app/api-reference/functions/generate-static-params). ```tsx filename="layout.tsx | page.tsx" switcher export const dynamicParams = true // true | false ``` ```js filename="layout.js | page.js | route.js" switcher export const dynamicParams = true // true | false ``` * **`true`** (default): Dynamic segments not included in `generateStaticParams` are generated on demand. * **`false`**: Dynamic segments not included in `generateStaticParams` will return a 404. > **Good to know**: > > * This option replaces the `fallback: true | false | blocking` option of `getStaticPaths` in the `pages` directory. > * To statically render all paths the first time they're visited, you'll need to return an empty array in `generateStaticParams` or utilize `export const dynamic = 'force-static'`. > * When `dynamicParams = true`, the segment uses [Streaming Server Rendering](/docs/app/getting-started/linking-and-navigating#streaming). ### `revalidate` Set the default revalidation time for a layout or page. This option does not override the `revalidate` value set by individual `fetch` requests. ```tsx filename="layout.tsx | page.tsx | route.ts" switcher export const revalidate = false // false | 0 | number ``` ```js filename="layout.js | page.js | route.js" switcher export const revalidate = false // false | 0 | number ``` * **`false`** (default): The default heuristic to cache any `fetch` requests that set their `cache` option to `'force-cache'` or are discovered before a [Dynamic API](/docs/app/getting-started/partial-prerendering#dynamic-rendering#dynamic-apis) is used. Semantically equivalent to `revalidate: Infinity` which effectively means the resource should be cached indefinitely. It is still possible for individual `fetch` requests to use `cache: 'no-store'` or `revalidate: 0` to avoid being cached and make the route dynamically rendered. Or set `revalidate` to a positive number lower than the route default to increase the revalidation frequency of a route. * **`0`**: Ensure a layout or page is always [dynamically rendered](/docs/app/getting-started/partial-prerendering#dynamic-rendering) even if no Dynamic APIs or uncached data fetches are discovered. This option changes the default of `fetch` requests that do not set a `cache` option to `'no-store'` but leaves `fetch` requests that opt into `'force-cache'` or use a positive `revalidate` as is. * **`number`**: (in seconds) Set the default revalidation frequency of a layout or page to `n` seconds. > **Good to know**: > > * The revalidate value needs to be statically analyzable. For example `revalidate = 600` is valid, but `revalidate = 60 * 10` is not. > * The revalidate value is not available when using `runtime = 'edge'`. > * In Development, Pages are *always* rendered on-demand and are never cached. This allows you to see changes immediately without waiting for a revalidation period to pass. #### Revalidation Frequency * The lowest `revalidate` across each layout and page of a single route will determine the revalidation frequency of the *entire* route. This ensures that child pages are revalidated as frequently as their parent layouts. * Individual `fetch` requests can set a lower `revalidate` than the route's default `revalidate` to increase the revalidation frequency of the entire route. This allows you to dynamically opt-in to more frequent revalidation for certain routes based on some criteria. ### `fetchCache`
This is an advanced option that should only be used if you specifically need to override the default behavior. By default, Next.js **will cache** any `fetch()` requests that are reachable **before** any [Dynamic APIs](/docs/app/getting-started/partial-prerendering#dynamic-rendering#dynamic-apis) are used and **will not cache** `fetch` requests that are discovered **after** Dynamic APIs are used. `fetchCache` allows you to override the default `cache` option of all `fetch` requests in a layout or page. ```tsx filename="layout.tsx | page.tsx | route.ts" switcher export const fetchCache = 'auto' // 'auto' | 'default-cache' | 'only-cache' // 'force-cache' | 'force-no-store' | 'default-no-store' | 'only-no-store' ``` ```js filename="layout.js | page.js | route.js" switcher export const fetchCache = 'auto' // 'auto' | 'default-cache' | 'only-cache' // 'force-cache' | 'force-no-store' | 'default-no-store' | 'only-no-store' ``` * **`'auto'`** (default): The default option to cache `fetch` requests before Dynamic APIs with the `cache` option they provide and not cache `fetch` requests after Dynamic APIs. * **`'default-cache'`**: Allow any `cache` option to be passed to `fetch` but if no option is provided then set the `cache` option to `'force-cache'`. This means that even `fetch` requests after Dynamic APIs are considered static. * **`'only-cache'`**: Ensure all `fetch` requests opt into caching by changing the default to `cache: 'force-cache'` if no option is provided and causing an error if any `fetch` requests use `cache: 'no-store'`. * **`'force-cache'`**: Ensure all `fetch` requests opt into caching by setting the `cache` option of all `fetch` requests to `'force-cache'`. * **`'default-no-store'`**: Allow any `cache` option to be passed to `fetch` but if no option is provided then set the `cache` option to `'no-store'`. This means that even `fetch` requests before Dynamic APIs are considered dynamic. * **`'only-no-store'`**: Ensure all `fetch` requests opt out of caching by changing the default to `cache: 'no-store'` if no option is provided and causing an error if any `fetch` requests use `cache: 'force-cache'` * **`'force-no-store'`**: Ensure all `fetch` requests opt out of caching by setting the `cache` option of all `fetch` requests to `'no-store'`. This forces all `fetch` requests to be re-fetched every request even if they provide a `'force-cache'` option. #### Cross-route segment behavior * Any options set across each layout and page of a single route need to be compatible with each other. * If both the `'only-cache'` and `'force-cache'` are provided, then `'force-cache'` wins. If both `'only-no-store'` and `'force-no-store'` are provided, then `'force-no-store'` wins. The force option changes the behavior across the route so a single segment with `'force-*'` would prevent any errors caused by `'only-*'`. * The intention of the `'only-*'` and `'force-*'` options is to guarantee the whole route is either fully static or fully dynamic. This means: * A combination of `'only-cache'` and `'only-no-store'` in a single route is not allowed. * A combination of `'force-cache'` and `'force-no-store'` in a single route is not allowed. * A parent cannot provide `'default-no-store'` if a child provides `'auto'` or `'*-cache'` since that could make the same fetch have different behavior. * It is generally recommended to leave shared parent layouts as `'auto'` and customize the options where child segments diverge.
### `runtime` We recommend using the Node.js runtime for rendering your application, and the Edge runtime for Middleware. ```tsx filename="layout.tsx | page.tsx | route.ts" switcher export const runtime = 'nodejs' // 'nodejs' | 'edge' ``` ```js filename="layout.js | page.js | route.js" switcher export const runtime = 'nodejs' // 'nodejs' | 'edge' ``` * **`'nodejs'`** (default) * **`'edge'`** ### `preferredRegion` ```tsx filename="layout.tsx | page.tsx | route.ts" switcher export const preferredRegion = 'auto' // 'auto' | 'global' | 'home' | ['iad1', 'sfo1'] ``` ```js filename="layout.js | page.js | route.js" switcher export const preferredRegion = 'auto' // 'auto' | 'global' | 'home' | ['iad1', 'sfo1'] ``` Support for `preferredRegion`, and regions supported, is dependent on your deployment platform. > **Good to know**: > > * If a `preferredRegion` is not specified, it will inherit the option of the nearest parent layout. > * The root layout defaults to `all` regions. ### `maxDuration` By default, Next.js does not limit the execution of server-side logic (rendering a page or handling an API). Deployment platforms can use `maxDuration` from the Next.js build output to add specific execution limits. **Note**: This setting requires Next.js `13.4.10` or higher. ```tsx filename="layout.tsx | page.tsx | route.ts" switcher export const maxDuration = 5 ``` ```js filename="layout.js | page.js | route.js" switcher export const maxDuration = 5 ``` > **Good to know**: > > * If using [Server Actions](/docs/app/getting-started/updating-data), set the `maxDuration` at the page level to change the default timeout of all Server Actions used on the page. ### `generateStaticParams` The `generateStaticParams` function can be used in combination with [dynamic route segments](/docs/app/api-reference/file-conventions/dynamic-routes) to define the list of route segment parameters that will be statically generated at build time instead of on-demand at request time. See the [API reference](/docs/app/api-reference/functions/generate-static-params) for more details. ## Version History | Version | | | ------------ | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `v15.0.0-RC` | `export const runtime = "experimental-edge"` deprecated. A [codemod](/docs/app/guides/upgrading/codemods#transform-app-router-route-segment-config-runtime-value-from-experimental-edge-to-edge) is available. | --- For an index of all available documentation, see [/docs/15/llms.txt](/docs/15/llms.txt)