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Principles of using cookies on the website

Principles of using cookies on the website


A cookie is a short text file that a visited website stores in your browser. Allows the site to record information about your visit. This may make the next visit easier for you and the site more useful.

For example, we use cookies to remember your preferred language, to select relevant ads, to track the number of visitors to the site, to facilitate registration for our services, to protect your data and to remember your ad settings.

This page describes the types of cookies that Google uses. It also explains how Google and our partners use cookies to serve ads. You can find more information about the protection of your privacy in connection with cookies and other data in our privacy policy.


Some or all of the listed cookies may be stored in your browser. If you want to manage the use of cookies, you can refuse the use of certain cookies at g.co/privacytools through Google personalization settings. You can also manage cookies in your browser (although mobile browsers don't usually offer this option). In Chrome, for example, you can go to chrome://settings/cookies.


Cookies are used to interact with the service or website and to access basic features of the service or website. These features include language preferences, optimization (to manage and improve the service), and managing user session information (such as shopping cart content).

Some cookies are used to manage user preferences. E.g. most Google users have a cookie called NID in their browser. It contains a unique ID that Google uses to remember your settings and other information, such as your preferred language, how many search results you want to see on one page (such as 10 or 20), and whether you want Google SafeSearch filtering turned on. The NID file expires 6 months after the user last uses it. The VISITOR_INFO1_LIVE cookie is used on YouTube for similar purposes, which also helps detect and troubleshoot service issues.

YouTube uses the PREF cookie to store information about the user, such as their preferred page configuration and playback preferences (autoplay, shuffle, player size). For YouTube Music, these preferences include volume, repeat mode, and auto play. This file expires 8 months after the user last used it.

Some cookies are used to manage and enhance the user experience during a single session. E.g. The YSC cookie on YouTube is used to remember user input and associate user actions. This file exists as long as the user has an open browser. The pm_sess file, which exists for 30 minutes, is also related to user session management.

Some cookies improve the performance of Google services. E.g. the CGIC file improves the display of search results by automatically completing search queries based on the user's original input. It has a shelf life of 6 months.


Cookies used for security authenticate users, prevent fraud and protect users when using the service.

Some cookies are used to authenticate users to ensure that only the owner of a particular account can sign in. For example, we use cookies called SIDs and HSIDs, which contain digitally signed and encrypted records of a user's Google Account ID and the time of their last login. The combination of these two cookies allows us to block many types of attacks (such as attempts to steal the content of forms you submit on Google).

Some cookies prevent spam, fraud or abuse. E.g. the pm_sess and YSC files ensure that requests within one browsing session are made by the user and not by other sites. Both files prevent malicious websites from acting without or with the user's knowledge.


The cookies used for analysis help to collect data on the basis of which the services understand the interactions of users with the service. Thanks to these statistics, services can improve their content and offer better features.

These cookies allow the website to find out how visitors use it. E.g. Google Analytics (which helps website and app owners to understand how visitors use it) uses a set of cookies to collect information and report on site usage without Google knowing any personally identifiable information about each visitor. The main cookie used by Google Analytics is the _ga file. It allows the service to distinguish individual users and has a shelf life of two years. It is used by all sites that implement Google Analytics, including Google services.

Analytics cookies like these are also used by Google services, and others like NID in Google Search or VISITOR_INFO1_LIVE on YouTube.


Google uses cookies to serve ads, including displaying, rendering, and personalizing them (depending on your ad settings at g.co/adsettings). It also uses them to limit the number of times an ad is displayed to a single user, to ignore ads that the user does not want to see, and to measure the effectiveness of the ads.

  • A NID file is used to show Google ads to users who are not signed in to Google services,
  • IDE and ANID cookies are used to display Google ads on third-party websites.

Other Google services, such as YouTube, may also use these files (along with others such as VISITOR_INFO1_LIVE) to serve more relevant ads.

If you've enabled personalized ads, your settings will be stored in the ANID file for 13 months in the European Economic Area (EEA), Switzerland and the United Kingdom, and 24 months elsewhere. If you have disabled personalized ads, the settings will be saved in the ANID file until 2030. The NID file will expire 6 months after the user last used it. The IDE is valid for 13 months in the EEA, Switzerland and the United Kingdom, and 24 months elsewhere.

Some cookies used to serve ads are for users who are signed in to Google services. E.g. The DSID is used to identify the logged in user on third-party websites and to remember whether the user has agreed to personalize the ads. It has a shelf life of 2 weeks.

Through the Google advertising platform, businesses can run ads on Google as well as third-party websites that partner with Google.

Some cookies are used by Google to serve ads on third-party websites and are set on the domain of the website you visit. E.g. _gads allows sites to display Google ads, including personalized ads. Cookies starting with _gac_ come from Google Analytics and are used by advertisers to measure user activity and the performance of their advertising campaigns. The _gads file has a shelf life of 13 months and the _gac_ files have a shelf life of 90 days.

Some cookies are used to measure the performance of campaigns and the conversion rates of Google ads on the site you're visiting. E.g. Cookies starting with _gcl_ come from Google Analytics and are used primarily by advertisers to measure the number of actions taken on the site after clicking on an ad (such as whether a user has purchased something). Conversion rate cookies are not used for personalized ads. _Gcl_ files have a shelf life of 90 days.


Personalization cookies enhance the user experience with personalized content and features.

Depending on your settings at g.co/privacytools, some cookies may make better recommendations available on certain services. E.g. VISITOR_INFO1_LIVE makes personalized recommendations on YouTube available based on past views and searches. The NID file, in turn, exposes personalized AutoComplete features in Search when users enter search queries. These cookies expire 6 months after the last use by the user.


Most browsers allow you to control how cookies are set and used when browsing, and allow you to delete cookies and browsing data. In addition, your browser may offer cookie management on individual websites. E.g. Google Chrome settings allow you to delete existing cookies, allow or block all cookies, and set cookie preferences for individual websites. In addition, Chrome and other types of browsers offer incognito mode, which doesn't save your web history or cookies when you close all incognito windows.

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