Next.js Error Tracking installation

Install with the wizard

Run this command in your project directory to add PostHog to your Next.js project. The wizard detects your framework, installs the SDK, and sets up your first events.

Learn more

Or set it up manually by following the rest of this guide.

Install the package

Required

Install the PostHog JavaScript library using your package manager:

npm install posthog-js
yarn add posthog-js
pnpm add posthog-js
bun add posthog-js

Add environment variables

Required

Add your PostHog project token and host to your .env.local file and to your hosting provider (e.g. Vercel, Netlify). These values need to start with NEXT_PUBLIC_ to be accessible on the client-side.

.env.local
NEXT_PUBLIC_POSTHOG_PROJECT_TOKEN=<ph_project_token>
NEXT_PUBLIC_POSTHOG_HOST=https://us.i.posthog.com

Initialize PostHog

Required

Choose the integration method based on your Next.js version and router type.

If you're using Next.js 15.3+, you can use instrumentation-client.ts for a lightweight, fast integration:

instrumentation-client.ts
import posthog from 'posthog-js'

posthog.init(process.env.NEXT_PUBLIC_POSTHOG_PROJECT_TOKEN!, {
    api_host: process.env.NEXT_PUBLIC_POSTHOG_HOST,
    defaults: '2026-08-30'
})

For the App router, create a providers.tsx file in your app folder. The posthog-js library needs to be initialized on the client-side using the 'use client' directive:

app/providers.tsx
'use client'

import { usePathname, useSearchParams } from "next/navigation"
import { useEffect } from "react"

import posthog from 'posthog-js'
import { PostHogProvider as PHProvider } from '@posthog/react'

export function PostHogProvider({ children }: { children: React.ReactNode }) {
  useEffect(() => {
    posthog.init(process.env.NEXT_PUBLIC_POSTHOG_PROJECT_TOKEN as string, {
      api_host: process.env.NEXT_PUBLIC_POSTHOG_HOST,
      defaults: '2026-08-30'
    })
  }, [])

  return (
    <PHProvider client={posthog}>
      {children}
    </PHProvider>
  )
}

Then import the PostHogProvider component in your app/layout.tsx and wrap your app with it:

app/layout.tsx
import './globals.css'
import { PostHogProvider } from './providers'

export default function RootLayout({ children }: { children: React.ReactNode }) {
  return (
    <html lang="en">
      <body>
        <PostHogProvider>
          {children}
        </PostHogProvider>
      </body>
    </html>
  )
}

For the Pages router, integrate PostHog at the root of your app in pages/_app.tsx:

pages/_app.tsx
import { useEffect } from 'react'
import { Router } from 'next/router'
import posthog from 'posthog-js'
import { PostHogProvider } from '@posthog/react'
import type { AppProps } from 'next/app'

export default function App({ Component, pageProps }: AppProps) {

  useEffect(() => {
    posthog.init(process.env.NEXT_PUBLIC_POSTHOG_PROJECT_TOKEN as string, {
      api_host: process.env.NEXT_PUBLIC_POSTHOG_HOST,
      defaults: '2026-08-30',
      loaded: (posthog) => {
        if (process.env.NODE_ENV === 'development') posthog.debug()
      }
    })
  }, [])

  return (
    <PostHogProvider client={posthog}>
      <Component {...pageProps} />
    </PostHogProvider>
  )
}

Defaults option

The defaults option automatically configures PostHog with recommended settings for new projects. See SDK defaults for details.

Accessing PostHog on the client

Recommended

Once initialized in instrumentation-client.ts, import posthog from posthog-js anywhere and call the methods you need:

app/checkout/page.tsx
'use client'

import posthog from 'posthog-js'

export default function CheckoutPage() {
    function handlePurchase() {
        posthog.capture('purchase_completed', { amount: 99 })
    }

    return <button onClick={handlePurchase}>Complete purchase</button>
}

Use the usePostHog hook to access PostHog in client components:

app/checkout/page.tsx
'use client'

import { usePostHog } from '@posthog/react'

export default function CheckoutPage() {
    const posthog = usePostHog()

    function handlePurchase() {
        posthog.capture('purchase_completed', { amount: 99 })
    }

    return <button onClick={handlePurchase}>Complete purchase</button>
}

Capture client-side exceptions

Required

PostHog can automatically capture unhandled exceptions in your Next.js app using the JavaScript Web SDK. Turn it on with capture_exceptions: true in your posthog.init call:

instrumentation-client.js
posthog.init(process.env.NEXT_PUBLIC_POSTHOG_PROJECT_TOKEN, {
  api_host: process.env.NEXT_PUBLIC_POSTHOG_HOST,
  capture_exceptions: true,
})

It is also possible to manually capture exceptions using the captureException method:

JavaScript
posthog.captureException(error, additionalProperties)

Manual capture is very useful if you already use error boundaries to handle errors in your app:

Next.js uses error boundaries to handle uncaught exceptions by rendering a fallback UI instead of the crashing components. To set one up, create a error.tsx file in any of your route directories. This triggers when there is an error rendering your component. An error boundary catches the error before autocapture sees it, so add the capture to every error.tsx your app has. It should look like this:

error.tsx
"use client"
import posthog from "posthog-js"
import { useEffect } from "react"

export default function Error({
  error,
  reset,
}: {
  error: Error & { digest?: string }
  reset: () => void
}) {
  useEffect(() => {
    posthog.captureException(error)
  }, [error])
  return (
    ...
  )
}

Also add the capture to a Global Error component at app/global-error.tsx, and create one if your app has none: it catches errors in the root layout and in the first render, before autocapture loads.

app/global-error.tsx
'use client'
import posthog from "posthog-js"
import NextError from "next/error"
import { useEffect } from "react"

export default function GlobalError({
  error,
  reset,
}: {
  error: Error & { digest?: string }
  reset: () => void
}) {
  useEffect(() => {
    posthog.captureException(error)
  }, [error])
  return (
    // global-error must include html and body tags
    <html>
      <body>
        {/* `NextError` is the default Next.js error page component */}
        <NextError statusCode={0} />
      </body>
    </html>
  )
}

For Pages Router, you can use React's Error Boundaries to catch JavaScript errors anywhere in the component tree. Create a custom error boundary component and report errors to PostHog in the componentDidCatch method:

components/ErrorBoundary.tsx
componentDidCatch(error, errorInfo) {
  posthog.captureException(error)
}

Then wrap your app or specific components with the error boundary:

pages/_app.tsx
import type { AppProps } from 'next/app'
import ErrorBoundary from '../components/ErrorBoundary'

export default function App({ Component, pageProps }: AppProps) {
  return (
    <ErrorBoundary>
      <Component {...pageProps} />
    </ErrorBoundary>
  )
}

Installing PostHog SDK for server-side

Required

Next.js enables you to both server-side render pages and add server-side functionality. To capture server-side exceptions, use @posthog/next for the errors Next.js reports and the Node SDK for everything else.

First, install @posthog/next 0.11.0+ and posthog-node 5.61.1+, and upgrade posthog-js to 1.445.1+ if yours is older:

npm install @posthog/next posthog-node
yarn add @posthog/next posthog-node
pnpm add @posthog/next posthog-node
bun add @posthog/next posthog-node

Then create a lib/posthog-server.js file that initializes PostHog from posthog-node. With enableExceptionAutocapture, it captures uncaught exceptions and unhandled promise rejections. Turn it on for the Node.js runtime only: the edge runtime cannot register process listeners, so the client would fail to start there.

This looks like this:

lib/posthog-server.js
import { PostHog } from 'posthog-node'

let posthogServer = null

export function getPostHogServer() {
  posthogServer ??= new PostHog(process.env.NEXT_PUBLIC_POSTHOG_PROJECT_TOKEN, {
    host: process.env.NEXT_PUBLIC_POSTHOG_HOST,
    flushAt: 1,
    flushInterval: 0,
    // Uncaught exceptions and unhandled promise rejections, on the Node.js runtime only
    enableExceptionAutocapture: process.env.NEXT_RUNTIME === 'nodejs',
  })
  return posthogServer
}

You can now use the getPostHogServer function to capture exceptions your server-side code handles itself. Pass the user's distinct ID when you know it:

JavaScript
const posthog = getPostHogServer()
try {
  throw new Error('This is a test exception for error tracking')
} catch (error) {
  posthog.captureException(error, 'user_distinct_id', { source: 'test' })
}

Verify server-side exceptions
Recommended
You should also see events and exceptions in PostHog coming from your server-side code in the activity feed.

Check for server events in PostHog

Capturing server-side exceptions

Required

To capture errors that occur in your server-side code, set up an instrumentation.ts file at the root of your project (or in src/). Next.js calls its onRequestError hook when a Server Component, Route Handler, or Server Action throws. createOnRequestError returns that hook, and links each error to the user and session. register() starts the posthog-node client when the server starts.

This looks like this:

instrumentation.js
import { createOnRequestError } from '@posthog/next'
import { getPostHogServer } from './lib/posthog-server'

export function register() {
  if (process.env.NEXT_RUNTIME === 'nodejs') {
    getPostHogServer()
  }
}

export const onRequestError = createOnRequestError({
  apiKey: process.env.NEXT_PUBLIC_POSTHOG_PROJECT_TOKEN,
  host: process.env.NEXT_PUBLIC_POSTHOG_HOST,
})

onRequestError misses errors thrown in proxy.ts and in Node.js middleware. If your app has either, wrap it with withPostHogProxy:

proxy.ts
import { NextResponse } from 'next/server'
import type { NextRequest } from 'next/server'
import { withPostHogProxy } from '@posthog/next'

// On Next.js 15 and earlier, this is middleware.ts with `export const middleware`
export const proxy = withPostHogProxy(
  async (request: NextRequest) => {
    // Your existing proxy code
    return NextResponse.next()
  },
  {
    apiKey: process.env.NEXT_PUBLIC_POSTHOG_PROJECT_TOKEN,
    host: process.env.NEXT_PUBLIC_POSTHOG_HOST,
  }
)

Errors thrown in after() callbacks do not reach onRequestError either. If your app imports after from next/server, capture inside each callback:

app/api/orders/route.ts
import { after } from 'next/server'
import { getPostHogServer } from '@/lib/posthog-server'

after(async () => {
  try {
    await sendReceipt(order)
  } catch (error) {
    await getPostHogServer().captureExceptionImmediate(error)
    throw error
  }
})

Next.js 14 and earlier run instrumentation.js only with the instrumentationHook flag. They never call onRequestError, so leave it out, and upgrade to capture Server Component, Route Handler and Server Action errors:

next.config.js
module.exports = {
  // Only on Next.js 14 and earlier: later versions run instrumentation.js without it
  experimental: { instrumentationHook: true },
}

You can find a full example of both this and client-side error tracking in our Next.js error monitoring tutorial.

Verify error tracking
Recommended
Confirm events are being sent to PostHog
Before proceeding, let's make sure exception events are being captured and sent to PostHog. You should see events appear in the activity feed.
Check for exceptions in PostHog
8
Upload source maps
Required
Great, you're capturing exceptions! If you serve minified bundles, the next step is to upload source maps to generate accurate stack traces.
Let's continue to the next section.
Upload source maps

Next.js Error Tracking installation

Install with the wizard

Install the package

Add environment variables

Initialize PostHog

Accessing PostHog on the client

Capture client-side exceptions

Installing PostHog SDK for server-side

Verify server-side exceptions

Capturing server-side exceptions

Verify error tracking

Upload source maps

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