Trace your commute

Practical privacy steps

Send an opt-out signal with Global Privacy Control

Enable Firefox GPC, understand California recognition and separate an opt-out signal from blocking or deleting data.

Sources checked .

Conceptual illustration

What the signal asks a website to do

Global Privacy Control, or GPC, sends a browser preference about the sale or sharing of personal information. California DOJ says covered businesses must honor it as a valid opt-out request. The cited legal explanation concerns California coverage; it does not establish one rule for every website worldwide. California DOJ: GPC scope

Firefox desktop: turn the signal on

  1. Open Firefox Settings from the browser menu, then choose Privacy & Security. Mozilla documents GPC support beginning with Firefox 120. Mozilla: GPC settings
  2. Find Website Privacy Preferences, or Additional protections in the other layout shown in Mozilla's guide. Enable the checkbox labeled Tell websites not to sell or share my data. Firefox saves the change automatically. Mozilla: GPC settings
  3. Use the linked Mozilla instructions for the installed version if its layout differs. Do not substitute the older Do Not Track option: Mozilla says that option was removed from Firefox settings in version 135. Mozilla: GPC settings

Check mobile support separately

CalPrivacy notes that some browsers do not support opt-out preference signals on mobile. Check the browser's documentation for the actual device, rather than assuming a desktop checkbox establishes the phone's setting. CalPrivacy: opt-out preference signals

Keep tracking protection and deletion separate

Mozilla explains that GPC communicates a request rather than blocking trackers. Its tracking protection is a separate control. Enabling the signal does not by itself verify what a website collected or how it responded. Mozilla: GPC settings

CalPrivacy describes the signal as an opt-out from sale or sharing. Use the separate broker and data-rights guides when the intended action is a deletion request, and keep the service's response. CalPrivacy: opt-out preference signals

A company example of scope

GM says its web GPC response changes certain website cookies and advertising technologies. Its policy separately lists connected-vehicle controls. Treat the browser signal and the vehicle's settings as different choices. GM: U.S. privacy controls

Questions and answers

Will GPC stop all tracking?

No. Mozilla describes a preference signal and warns that websites can still track. Mozilla: GPC settings

Is this just the old Do Not Track checkbox?

Mozilla documents GPC separately and says Firefox removed the Do Not Track setting in version 135. Mozilla: GPC settings

Must every company worldwide honor this signal?

The California DOJ source explains duties for businesses covered by California law. It does not establish universal coverage. California DOJ: GPC scope

Sources and scope

Mozilla desktop instructions and California official guidance checked 10-23-2026. Mozilla shows two settings layouts. No user browser preferences were changed and no website's legal compliance was tested.

Keep exploring