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Delba de OliveiraGitHubVercel <vercel[bot]@users.noreply.github.com>Joseph
c2b4c0815c Unify caching story across the docs (#90149)
This PRs unifies the caching story across the docs, making Cache
Components the happy path, while still providing guidance to users in
the old model. However, instead of explaining the old model and its
caching layers, we've created a new guide focusing on what APIs to use
and when.

This follow-up PR aligns terminology across the docs:
https://github.com/vercel/next.js/pull/90589

## IA updates

Getting Started section: 

- Improves Getting Started progression:
- **Before:** CC → Fetching Data → Updating Data → Caching and
Revalidating (old and new model mixed)
- **After:** Fetching Data (Dynamic) → Mutating Data (Dynamic) → Caching
with CC (Prerendering) → Revalidating with CC.
- New: `caching.mdx` (CC-first)
   - Structure: 
      - Enabling Cache Components
      - Data vs UI-level caching
      - Working with request time APIs
      - Passing request values to cached functions
      - Working with non-deterministic operations
      - Working with synchronous operations
      - How rendering works (PPR and static shell story)
- New: `revalidating.mdx` (CC-first)
   - Explains how to use `cacheLife` and `cacheTag`

Guides Section: 

- New: `caching-and-revalidating.mdx` (Previous Model)
- For users who are not using CC, includes `fetch` options and route
segment config
- Moves route segment config options that don't apply to CC from API
reference to this guide (for easy archiving in the future).
- New: `migrating-to-cache-components.mdx` (WIP)
- Del: `caching.mdx` 😌 

## Terminology

We should remove caching layers from the docs. Users only needed to be
exposed to them when they were configured independently, but the new CC
APIs work across layers.

To make it easier to review this PR, I'm consolidating terminology and
fixing broken links in a new PR:
https://github.com/vercel/next.js/pull/90589

---------

Co-authored-by: Vercel <vercel[bot]@users.noreply.github.com>
Co-authored-by: Joseph <[email protected]>
2026-03-03 13:14:24 +00:00

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---
title: useParams
description: API Reference for the useParams hook in the Pages Router.
---
`useParams` is a hook that lets you read a route's [dynamic params](/docs/pages/building-your-application/routing/dynamic-routes) filled in by the current URL.
```tsx filename="pages/shop/[slug].tsx" switcher
import { useParams } from 'next/navigation'
export default function ShopPage() {
const params = useParams<{ slug: string }>()
if (!params) {
// Render fallback UI while params are not yet available
return null
}
// Route -> /shop/[slug]
// URL -> /shop/shoes
// `params` -> { slug: 'shoes' }
return <>Shop: {params.slug}</>
}
```
```jsx filename="pages/shop/[slug].js" switcher
import { useParams } from 'next/navigation'
export default function ShopPage() {
const params = useParams()
if (!params) {
// Render fallback UI while params are not yet available
return null
}
// Route -> /shop/[slug]
// URL -> /shop/shoes
// `params` -> { slug: 'shoes' }
return <>Shop: {params.slug}</>
}
```
## Parameters
```tsx
const params = useParams()
```
`useParams` does not take any parameters.
## Returns
`useParams` returns an object containing the current route's filled in [dynamic parameters](/docs/pages/building-your-application/routing/dynamic-routes), or `null` during [prerendering](#behavior-during-prerendering).
- Each property in the object is an active dynamic segment.
- The property name is the segment's name, and the property value is what the segment is filled in with.
- The property value will either be a `string` or array of `string`s depending on the [type of dynamic segment](/docs/pages/building-your-application/routing/dynamic-routes).
- If the route contains no dynamic parameters, `useParams` returns an empty object.
For example:
| Route | URL | `useParams()` |
| ---------------------------- | ----------- | ------------------------- |
| `pages/shop/page.js` | `/shop` | `{}` |
| `pages/shop/[slug].js` | `/shop/1` | `{ slug: '1' }` |
| `pages/shop/[tag]/[item].js` | `/shop/1/2` | `{ tag: '1', item: '2' }` |
| `pages/shop/[...slug].js` | `/shop/1/2` | `{ slug: ['1', '2'] }` |
> **Good to know**: `useParams` is a [React Hook](https://react.dev/learn#using-hooks) and cannot be used with classes.
## Behavior
### Behavior during prerendering
For pages that are [statically optimized](/docs/pages/building-your-application/rendering/automatic-static-optimization), `useParams` will return `null` on the initial render. After hydration, the value will be updated to the actual params once the router is ready.
This is because params cannot be known during static generation for dynamic routes.
```tsx filename="pages/shop/[slug].tsx" switcher
import { useParams } from 'next/navigation'
export default function ShopPage() {
const params = useParams<{ slug: string }>()
if (!params) {
// Return a fallback UI while params are loading
// This prevents hydration mismatches
return <ShopPageSkeleton />
}
return <>Shop: {params.slug}</>
}
```
```jsx filename="pages/shop/[slug].js" switcher
import { useParams } from 'next/navigation'
export default function ShopPage() {
const params = useParams()
if (!params) {
// Return a fallback UI while params are loading
// This prevents hydration mismatches
return <ShopPageSkeleton />
}
return <>Shop: {params.slug}</>
}
```
### Using with `getServerSideProps`
When using [`getServerSideProps`](/docs/pages/building-your-application/data-fetching/get-server-side-props), the page is server-rendered on each request and `useParams` will return the actual params immediately:
```tsx filename="pages/shop/[slug].tsx" switcher
import { useParams } from 'next/navigation'
export default function ShopPage() {
const params = useParams<{ slug: string }>()
// With getServerSideProps, this fallback is never rendered because
// params is always available on the server. However, keeping
// the fallback allows this component to be reused on other pages
// that may not use getServerSideProps.
if (!params) {
return null
}
return <>Shop: {params.slug}</>
}
export async function getServerSideProps() {
return { props: {} }
}
```
```jsx filename="pages/shop/[slug].js" switcher
import { useParams } from 'next/navigation'
export default function ShopPage() {
const params = useParams()
// With getServerSideProps, this fallback is never rendered because
// params is always available on the server. However, keeping
// the fallback allows this component to be reused on other pages
// that may not use getServerSideProps.
if (!params) {
return null
}
return <>Shop: {params.slug}</>
}
export async function getServerSideProps() {
return { props: {} }
}
```
### Comparison with `router.query`
`useParams` only returns the dynamic route parameters, whereas [`router.query`](/docs/pages/api-reference/functions/use-router#router-object) from `useRouter` includes both dynamic parameters and query string parameters.
```tsx filename="pages/shop/[slug].tsx" switcher
import { useRouter } from 'next/router'
import { useParams } from 'next/navigation'
export default function ShopPage() {
const router = useRouter()
const params = useParams()
// URL -> /shop/shoes?color=red
// router.query -> { slug: 'shoes', color: 'red' }
// params -> { slug: 'shoes' }
// ...
}
```
```jsx filename="pages/shop/[slug].js" switcher
import { useRouter } from 'next/router'
import { useParams } from 'next/navigation'
export default function ShopPage() {
const router = useRouter()
const params = useParams()
// URL -> /shop/shoes?color=red
// router.query -> { slug: 'shoes', color: 'red' }
// params -> { slug: 'shoes' }
// ...
}
```
## Examples
### Sharing components with App Router
`useParams` from `next/navigation` works in both the Pages Router and App Router. This allows you to create shared components that work in either context:
```tsx filename="components/breadcrumb.tsx" switcher
import { useParams } from 'next/navigation'
// This component works in both pages/ and app/
export function Breadcrumb() {
const params = useParams<{ slug: string }>()
if (!params) {
// Fallback for Pages Router during prerendering
return <nav>Home / ...</nav>
}
return <nav>Home / {params.slug}</nav>
}
```
```jsx filename="components/breadcrumb.js" switcher
import { useParams } from 'next/navigation'
// This component works in both pages/ and app/
export function Breadcrumb() {
const params = useParams()
if (!params) {
// Fallback for Pages Router during prerendering
return <nav>Home / ...</nav>
}
return <nav>Home / {params.slug}</nav>
}
```
> **Good to know**: When using this component in the App Router, `useParams` never returns `null`, so the fallback branch will not be rendered.
## Version History
| Version | Changes |
| --------- | ----------------------- |
| `v13.3.0` | `useParams` introduced. |