Analytics
_pk_ses.<appID>.<domainHash>
Module: Analytics
Expires after: 30 minutes (can be changed)
Extends: Automatically
Type: First-party cookie
About: Shows an active session of the visitor. If the cookie isn’t present, the session has finished over 30 minutes ago and it was counted in a pk_id cookie.
_pk_id.<appID>.<domainHash>
Module: Analytics
Expires after: 13 months (can be changed)
Extends: No
Type: First-party cookie
About: Used to recognize visitors and hold their various properties.
Value: <visitorID>.<cookieCreationTimestamp>.<visitsCount>.<currentVisitTimestamp>.<lastVisitTimestamp>.<lastEcommerceOrderTimestamp>
_pk_cvar
Module: Analytics
Expires after: 30 minutes (can be changed)
Extends: No
Type: First-party cookie
About: Holds custom variables that were set during the previous page view. It’s not enabled by default. Requires calling the storeCustomVariablesInCookie() method on the Javascript tracker object.
Value: Custom variable keys and values.
app_id
Module: Analytics
Expires after: 365 days
Extends: Automatically
Type: First-party cookie
About: Used to pass a site or app ID between Piwik PRO’s modules: Analytics, Tag Manager, Audience Manager, Consent Manager, Administration.
Value: A site or app ID.
piwik_auth (deprecated)
Module: Analytics (versions below 16.0.0)
Expires after: 24 minutes (can be changed)
Extends: Automatically
Type: First-party cookie
About: Stores session information for Piwik PRO’s user interface (UI). As long as this cookie is valid and contains a login and a token_auth parameter, a visitor is considered as a logged-in visitor, and a PIWIK_SESSID cookie will be refreshed.
Value: login=<userLogin>:token_auth=<tokenHash>:_=<signature>
PIWIK_SESSID (deprecated)
Module: Analytics (versions below 16.0.0)
Expires after: 24 minutes (can be changed)
Extends: No
Type: First-party cookie
About: Stores a PHP session ID.
Value: A unique session identifier.
Tag Manager
_stg_debug / stg_debug
Module: Tag Manager
Expires after: 14 days
Extends: Automatically
Type: First-party cookie
About: Determines if the Tag Manager’s debugger should be displayed. A cookie is removed after you close the debugger.
Value: 1 when debug mode is turned on.
Created if: You use a stg_debug query parameter in the URL.
stg_traffic_source_priority
Module: Tag Manager
Expires after: 30 minutes
Extends: Automatically
Type: First-party cookie
About: Stores the type of traffic source that explains how the visitor reached your website.
Value:
Created if: You use the traffic source condition in a trigger.
stg_last_interaction
Module: Tag Manager
Expires after: 365 days
Extends: Automatically
Type: First-party cookie
About: Determines whether the last visitor’s session is still in progress or a new session has started.
Value: A timestamp of the last interaction a visitor had on your website.
Created if: You use a multiplicity condition in a trigger.
stg_returning_visitor
Module: Tag Manager
Expires after: 365 days
Extends: Automatically
Type: First-party cookie
About: Determines if the visitor has already been to your website — they are returning visitors.
Value: A timestamp of the last interaction a visitor had on your website.
Created if: You use a returning-visitor condition in a trigger.
stg_fired__<appID>
Module: Tag Manager
Expires after: The session ends. (Fixed idle time or after a browser is closed.)
Extends: No
Type: First-party cookie
About: Determines if the combination of a tag and trigger was fired during the current visitor’s session.
Value: A timestamp of the moment when a tag is fired.
Created if: You use a multiplicity condition in a trigger, and a trigger is set to fire a tag once per session. A cookie is created after the tag is fired.
stg_utm_campaign
Module: Tag Manager
Expires after: The session ends. (Fixed idle time or after a browser is closed.)
Extends: No
Type: First-party cookie
About: Stores a name of the campaign that directed the visitor to your website.
Value: An encoded value of an utm_campaign query parameter.
Created if: You use the campaign condition in a trigger, and a visitor enters your website from a campaign with an utm_campaign query parameter.
stg_pk_campaign
Module: Tag Manager
Expires after: The session ends. (Fixed idle time or after a browser is closed.)
Extends: No
Type: First-party cookie
About: Stores a name of the campaign that directed the visitor to your website.
Value: An encoded value of a pk_campaign query parameter.
Created if: You use the campaign condition in a trigger, and a visitor enters your website from a campaign with a pk_campaign query parameter.
stg_externalReferrer
Module: Tag Manager
Expires after: The session ends. (Fixed idle time or after a browser is closed.)
Extends: No
Type: First-party cookie
About: Stores an URL of a website that referred a visitor to your website.
Value: The window.location.origin value for a referral website.
Created if: You use the external referrer condition in a trigger, and a visitor enters your website from a referral website.
_stg_opt_out_simulate
Module: Tag Manager
Expires after: 365 days
Extends: Automatically
Type: First-party cookie
About: Used to simulate the behavior of the opt-out snippet in the debugger. It turns off all tracking tags in the tested domain.
Value:
Created if: You turn on opt-out simulation in debug mode.
_stg_optout
Module: Tag Manager
Expires after: 365 days
Extends: Automatically
Type: First-party cookie
About: Used to turn off all tracking tags in the tested domain.
Value:
Created if: A visitor opts out of tracking. (You use an opt-out snippet.)
stg_global_opt_out (deprecated)
Module: Tag Manager
Expires after: 365 days
Extends: Automatically
Type: Third-party cookie
About: Used to turn off all tracking tags on websites that belong to one Piwik PRO account.
Value:
Created if: A third-party cookie is set when a visitor opts out of tracking. (You use a global opt-out snippet.)
Local storage
In addition to cookies, Piwik PRO uses local storage in the visitor’s browser to stack some information. Here’s what is kept in that storage.
ppms_webstorage
Module: Tag Manager, Consent Manager and Analytics
About: Prevents visitor’s data loss that may happen because of some mechanisms used by browsers, for example, Safari’s ITP.
Value: A stringified object that contains information about created cookies for each module. It stores data about each created cookie, such as a key, value, expiry date, path, domain, and more. This is the same data that was used to create a cookie.
Created if: Each time a cookie is set in the visitor’s browser.
Removed if: A ppms_webstorage item isn’t removed automatically. But a visitor can delete it manually. Single entries in the object are removed after a corresponding cookie expires.
ppms_data_store
Module: Audience Manager
About: Stores information from forms on your website. After a visitor submits a form, the data is passed to Audience Manager. But if a form redirects a visitor to another page, data may be lost. Therefore form data is kept in the local storage as a backup. (A page where a visitor is redirected needs to have a form tracker, otherwise Piwik PRO can’t collect form data.)
Value: A JSON encoded object that contains:
Removed if: After the form tracker sends data to the server. It can happen right after a visitor submits a form or after a new page loads in their browser.