---
title: "Cannot revalidate during render, inside a cached function, or in `generateStaticParams`"
url: "https://nextjs.org/docs/messages/revalidate-in-use-cache"
docs_index: /docs/llms.txt
---



## Why This Error Occurred

The `revalidateTag()` and `revalidatePath()` functions invalidate cached data. To keep cache state consistent, call them from a Server Action or Route Handler. Next.js throws this error when you call either function during rendering, from a cached function, or from `generateStaticParams`.

```jsx filename="app/products/page.js" highlight={5}
import { revalidateTag } from 'next/cache'

export default async function Page() {
  const products = await db.products.findMany()
  revalidateTag('products', 'max') // Cannot revalidate during render

  return <p>{products.length} products</p>
}
```

## Possible Ways to Fix It

Call `revalidateTag()` or `revalidatePath()` from the Server Action or Route Handler itself. Do not call either function during rendering or from a function that uses the `use cache` directive or `unstable_cache()`.

```jsx filename="app/actions.js" highlight={6}
'use server'
import { revalidateTag } from 'next/cache'

export async function saveProduct(data) {
  await db.products.create(data)
  revalidateTag('products', 'max') // Runs outside any cached function
}
```

To tag the cache entry that this revalidates, call [`cacheTag()`](/docs/app/api-reference/functions/cacheTag) inside the function that uses the `use cache` directive to read the data.

## Useful Links

- [`revalidateTag()` function](/docs/app/api-reference/functions/revalidateTag)
- [`revalidatePath()` function](/docs/app/api-reference/functions/revalidatePath)
- [Revalidating data](/docs/app/getting-started/revalidating)
- [`use cache` directive](/docs/app/api-reference/directives/use-cache)