Next.js

Telemetry

Next.js collects completely anonymous telemetry data about general usage. Participation in this anonymous program is optional, and you may opt-out if you'd not like to share any information.

Why Is Telemetry Collected?

Next.js has grown considerably since its release, becoming the de-facto React Framework for developers.
Prior to telemetry collection, our improvement process has been very much a manual one.

For example, Vercel dogfoods many large React applications (e.g. https://vercel.com/, https://vercel.com/docs, https://nextjs.org). Additionally, we actively engage with the community to gather feedback.
However, this approach only allows us to collect feedback from a subset of users. This subset may have different needs and use-cases than you.

Telemetry allows us to accurately gauge Next.js feature usage, pain points, and customization across all users.
This data will let us better tailor Next.js to the masses, ensuring its continued growth, relevance, and best-in-class developer experience.
Furthermore, this will allow us to verify if improvements made to the framework are improving the baseline of all applications.

What Is Being Collected?

We track general usage information, such as Next.js plugins and build performance. Specifically, we track the following anonymously:

• Command invoked (next build, next dev, or next export)
• Version of Next.js
• General machine information (e.g. number of CPUs, macOS/Windows/Linux, whether or not the command was run within CI)
• What Next.js plugins are present in your project
• Duration of next build and size of application (total number of pages)

Note: This list is regularly audited to ensure its accuracy.

You can view exactly what is being collected by setting the following environment variable: NEXT_TELEMETRY_DEBUG=1.
When this environment variable is set, data will not be sent to us. The data will only be printed out to the stderr stream, prefixed with [telemetry].

An example telemetry event looks like this:

{
  "eventName": "NEXT_VERSION",
  "payload": {
    "version": "9.0.5-canary.2",
    "isDevelopment": false
  }
}

What about Sensitive Data (e.g. Secrets)?

We do not collect any metrics which may contain sensitive data.
This includes, but is not limited to: environment variables, file paths, contents of files, logs, or serialized JavaScript errors.

We take your privacy and our security very seriously. Next.js telemetry falls under the security disclosure policy.

Will This Data Be Shared?

The data we collect is completely anonymous, not traceable to the source, and only meaningful in aggregate form.
No data we collect is personally identifiable.

In the future, we plan to share relevant data with the community through public dashboards (or similar data representation formats).

How Do I Opt-Out?

You may opt out-by running next telemetry disable in the root of your project directory:

npx next telemetry disable

You may check the status of telemetry collection at any time by running next telemetry status in the root of your project directory:

npx next telemetry status

You may re-enable telemetry if you'd like to re-join the program by running the following in the root of your project directory:

npx next telemetry enable

You may also opt-out by setting an environment variable: NEXT_TELEMETRY_DISABLED=1.