GoogleChrome/lighthouse · error · LighthouseError

CRI_TIMEOUT

CRI_TIMEOUT

Error message

Timeout waiting for initial Debugger Protocol connection.

What it means

Error "Timeout waiting for initial Debugger Protocol connection." thrown in GoogleChrome/lighthouse.

Source

Thrown at core/lib/lh-error.js:405

  /* Protocol timeout failures
   * Requires an additional `protocolMethod` field for translation.
   */
  PROTOCOL_TIMEOUT: {
    code: 'PROTOCOL_TIMEOUT',
    message: UIStrings.protocolTimeout,
    lhrRuntimeError: true,
  },

  // DNS failure on main document (no resolution, timed out, etc)
  DNS_FAILURE: {
    code: 'DNS_FAILURE',
    message: UIStrings.dnsFailure,
    lhrRuntimeError: true,
  },

  /** A timeout in the initial connection to the debugger protocol. */
  CRI_TIMEOUT: {
    code: 'CRI_TIMEOUT',
    message: UIStrings.criTimeout,
    lhrRuntimeError: true,
  },

  /**
   * Error internal to Runner used when an artifact required for an audit is missing.
   * Requires an additional `artifactName` field for translation.
  */
  MISSING_REQUIRED_ARTIFACT: {
    code: 'MISSING_REQUIRED_ARTIFACT',
    message: UIStrings.missingRequiredArtifact,
  },

  /**
   * Error internal to Runner used when an artifact required for an audit was an error.
   * Requires additional `artifactName` and `errorMessage` fields for translation.
  */
  ERRORED_REQUIRED_ARTIFACT: {

View on GitHub (pinned to 9515cd4e58)

Solutions

1. Restart Chrome and re-run Lighthouse.
2. Make sure Chrome can launch with remote debugging enabled and no other process is using the debugging port.
3. Check for firewall or antivirus software blocking the DevTools protocol connection.

When it happens

Trigger: Raised when the initial connection to Chrome's Debugger Protocol does not complete in time.

Common situations: See trigger scenarios.

Understand the failure class

• Timeouts: ETIMEDOUT, deadlines, and hung requests — what actually expires when a request times out.

AI-assisted analysis of GoogleChrome/lighthouse@9515cd4e58 (2026-08-13). Data as JSON: /api/errors/5c9da0352d7bef07. Report an issue: GitHub.