A cookie is a small piece of text sent to your browser by a website that you visit. It helps the site remember information about your visit, which can make it easier to visit the site again and make the site more useful to you.
Types of cookies used by Google
Some or all of the cookies described below may be stored in your browser. To manage how cookies are used, you can refuse the use of certain cookies through your Google personalisation settings at any time by visiting g.co/privacytools. You can also manage cookies in your browser (though browsers for mobile devices may not offer this visibility). For example, if you use Google Chrome as your browser, you can visit chrome://settings/cookies.
Cookies used for functionality allow users to interact with a service or site to access features that are fundamental to that service. Things considered fundamental to the service include preferences like the user’s choice of language, product optimisations that help maintain and improve a service, and maintaining information relating to a user’s session, such as the content of a shopping basket.
Some cookies are used to maintain a user’s preferences. For example, most people who use Google services have a cookie called ‘NID’ in their browsers. This cookie contains a unique ID used to remember your preferences and other information, such as your preferred language, how many search results you prefer to have shown on a results page (for example, 10 or 20), and whether you want to have Google’s SafeSearch filter turned on. Each NID cookie expires six months from a user’s last use. A cookie called ‘VISITOR_INFO1_LIVE’ serves a similar purpose for YouTube and is also used to detect and resolve problems with the service.
YouTube uses the ‘PREF’ cookie to store information, such as a user’s preferred page configuration and playback preferences like autoplay, shuffle content and player size. For YouTube Music, these preferences include volume, repeat mode and auto-play. This cookie expires eight months from a user’s last use.
Some cookies are used to maintain and enhance a user’s experience during a specific browsing session. For example, ‘YSC’ is used by YouTube to remember user input and associate a user’s actions. This cookie lasts for as long as the user keeps their browser open. The cookie ‘pm_sess’ also helps maintain a user’s browser session and lasts for 30 minutes.
Some cookies improve the performance of Google services. For example, ‘CGIC’ improves the delivery of search results by auto-completing search queries based on a user’s initial input. This cookie lasts for six months.
Cookies used for security authenticate users, prevent fraud and protect users as they interact with a service.
Some cookies are used to authenticate users, helping to ensure that only the actual owner of an account can access that account. For example, cookies called ‘SID’ and ‘HSID’ contain digitally signed and encrypted records of a user’s Google Account ID and most recent sign-in time. The combination of these cookies allows us to block many types of attack, such as attempts to steal the content of forms submitted in Google services.
Some cookies are used to prevent spam, fraud and abuse. For example, the ‘pm_sess’ and ‘YSC’ cookies ensure that requests within a browsing session are made by the user and not by other sites. Both cookies prevent malicious sites acting without a user’s knowledge and as if they were that user.
Cookies used for analytics help collect data that allows services to understand how users interact with a particular service. These insights allow services both to improve content and to build better features that improve the user’s experience.
Some cookies help sites understand how their visitors engage with their properties. For example, Google Analytics, a Google product that helps site and app owners understand how people engage with a service, uses a set of cookies to collect information and report site usage statistics without personally identifying individual visitors to Google. ‘_ga’ is the main cookie used by Google Analytics. ‘_ga’ enables a service to distinguish one user from another and lasts for two years. It’s used by any site that implements Google Analytics, including Google services.
Google services also use analytics cookies like these, as well as others like ‘NID’ on Google Search and ‘VISITOR_INFO1_LIVE’ on YouTube.
- ‘NID’ is used for these purposes to show Google ads in Google services for signed-out users
- ‘IDE’ and ‘ANID’ are used for these purposes to show Google ads on non-Google sites
Other Google services like YouTube may also use these cookies and cookies like ‘VISITOR_INFO1_LIVE’ to show more relevant ads.
If you have personalised ads enabled, ‘ANID’ is used to remember this setting and lasts for 13 months in the European Economic Area (EEA), Switzerland and the United Kingdom (UK), and 24 months everywhere else. If you have disabled personalised ads, ‘ANID’ is used to store that setting until 2030. ‘NID’ expires six months from a user’s last use. ‘IDE’ lasts for 13 months in the EEA, Switzerland and the UK, and 24 months everywhere else.
Some cookies used for advertising are for users who sign in to use Google services. For example, ‘DSID’ is used to identify a signed-in user on non-Google sites and to remember whether the user has agreed to ad personalisation. It lasts for two weeks.
Through Google’s advertising platform, businesses can advertise in Google services as well as on non-Google sites that partner with Google.
Some cookies support Google showing ads on third-party sites, and are set in the domain of the website that you visit. For example, ‘_gads’ enables sites to show Google ads, including personalised ads. Cookies that start with ‘_gac_’ come from Google Analytics and are used by advertisers to measure user activity and the performance of their ad campaigns. The ‘_gads’ cookie lasts for 13 months and the ‘_gac_’ cookies last for 90 days.
Some cookies are used to measure ad and campaign performance and conversion rates for Google ads on a site that you visit. For example, cookies that start with ‘_gcl_’ come from Google Analytics, and are primarily used to help advertisers determine how many times users who click on their ads end up taking an action on their site, such as making a purchase. Cookies used for measuring conversion rates aren’t used to personalise ads. ‘_gcl_’ cookies last for 90 days.
Cookies used for personalisation enhance the user’s experience by providing personalised content and features.
Depending on your settings at g.co/privacytools, some cookies enable better recommendations within a service. For example, ‘VISITOR_INFO1_LIVE’ enables personalised recommendations on YouTube based on past views and searches. And ‘NID’ enables personalised autocomplete features in Search as users type search terms. These cookies expire six months after a user’s last use
Managing cookies in your browser
Most browsers allow you to manage how cookies are set and used as you’re browsing, and to clear cookies and browsing data. Also, your browser may have settings allowing you to manage cookies on a site-by-site basis. For example, Google Chrome’s settings allow you to delete existing cookies, allow or block all cookies and set cookie preferences for websites. Google Chrome also has Incognito mode, which doesn’t store your Chrome history of visited sites or cookies on your device after you close all incognito windows.