> ## Documentation Index
> Fetch the complete documentation index at: https://e2e.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Cloudflare Browser Run

> Run web targets in Cloudflare's hosted Chromium with the browserRun() browser provider.

`browserRun()` from `@e2e-dev/browser-run` gives each worker slot, or each test attempt, a Cloudflare-hosted Chromium browser.
Tests use the same web engine and fixtures.

## Connect your account

Create a [Cloudflare API token](https://developers.cloudflare.com/browser-run/cdp/) with `Browser Rendering - Edit` permission for your account.
Set `CLOUDFLARE_ACCOUNT_ID` and `CLOUDFLARE_API_TOKEN` in the environment where `e2e run` starts.

Install the provider alongside `e2e` and `@e2e-dev/web`:

<CodeGroup>
```bash npm
npm install --save-dev @e2e-dev/browser-run
```

```bash pnpm
pnpm add -D @e2e-dev/browser-run
```

```bash bun
bun add -d @e2e-dev/browser-run
```
</CodeGroup>

Set the target's browser:

```ts title="e2e.config.ts"

export default {
  targets: [{
    name: 'cloudflare',
    engine: web({ browser: browserRun() }),
    app: { url: 'https://staging.example.com' },
  }],
  workers: 2,
} satisfies E2EConfig;
```

Use a public HTTPS app URL. A hosted browser cannot reach the runner's `localhost`; expose local apps through a tunnel.

## Set browser lifetime

| Option | Default | Meaning |
| --- | --- | --- |
| `scope` | `'worker'` | One browser per worker slot. `'attempt'` leases a fresh browser for every attempt and retry. |
| `keepAlive` | `600000` | Inactivity timeout in milliseconds, from `10000` to `1200000`. |

The timeout counts time without CDP commands, even while connected. Increase `keepAlive` when a test can pause longer than ten minutes.

Worker scope creates an isolated context for every attempt.
Attempt scope uses the fresh browser's default context and supports reconnecting to that browser after a transport drop.
The [per-attempt provider limits](https://e2e.com/docs/browser#hosted-browsers) apply.

Sessions are deleted during teardown. If the runner exits before cleanup, the inactivity timeout ends the browser.

## Check compatibility

Chromium, navigation, locators, network routes, cookies, screenshots, and the web engine's screencast video use CDP.
CDP authorization headers authenticate the browser connection and do not become page request headers.

History navigation can time out on Browser Run while waiting for the page's `load` event after `browser.back()` or `browser.forward()`.

Remote file downloads are not supported. Browser Run exposes no browser filesystem API for the provider to read.
Cloudflare-native session recordings are not attached to reports.
When [video](https://e2e.com/docs/reference/config#video) is enabled, the web engine records a per-attempt WebM screencast.

Keep `workers` within your account's [concurrency and acquisition limits](https://developers.cloudflare.com/browser-run/limits/).
An HTTP `401` or `403` names the token permission to check.

## Next

<CardGroup cols={2}>
  <Card title="Hosted browsers" href="/browser#hosted-browsers">Understand provider scopes and isolation.</Card>
  <Card title="Web engine" href="/web">Configure viewports, app access, and video.</Card>
</CardGroup>