---
url: https://simpledatalogs.com/docs/quickstarts/nextjs.md
description: >-
  Add simpledatalogs to a Next.js app in one minute, with page views, sessions
  and errors captured by one line.
---

# Next.js

## Install

```sh
npx simpledatalogs init
```

The command finds your Next.js app, adds the key to `.env.local`, writes `instrumentation-client.ts`, shows you the diff first, and sends a test event. Then install the package:

```sh
npm install simpledatalogs
```

## Or by hand

```sh
# .env.local
NEXT_PUBLIC_SIMPLEDATALOGS_KEY=sdl_pub_…
```

```ts
// instrumentation-client.ts (next to app/, or in src/)
import { init } from 'simpledatalogs'

init({ key: process.env.NEXT_PUBLIC_SIMPLEDATALOGS_KEY, autocapture: true })
```

`instrumentation-client` runs in the browser before your app (Next.js 15.3 or later). On older versions, call `init()` once in a client component rendered by your root layout.

## Send everything, or only what you choose

* **Everything:** `autocapture: true`, as above.
* **Only your own events:** leave `autocapture` out and call `track()`:

```ts
import { init } from 'simpledatalogs'

export const sdl = init({ key: process.env.NEXT_PUBLIC_SIMPLEDATALOGS_KEY })

sdl.track('signup', { plan: 'pro' })
```

## In the first minute

* `session_start`, then a `page_view` with `path`, `title`, `referrer` and any `utm_*` parameters.
* A `page_view` for every client-side navigation (`<Link>`, `router.push`, back and forward).
* Uncaught errors and unhandled promise rejections on the **Logs** tab, with their stack.

## Autocapture defaults

| Feature | `autocapture: true` |
|---|---|
| Page views (App and Pages Router navigation) | on |
| Sessions (`session_id`, 30 idle minutes) | on |
| Errors and unhandled rejections | on |
| Outbound link clicks | off (`autocapture: { outboundLinks: true }`) |
| Do Not Track / Global Privacy Control | respected: nothing automatic is sent |

No cookies: the session id lives in `sessionStorage`. Every option is in the [JavaScript SDK](/sdks/javascript#autocapture) reference.