What is the gwcc cookie?
gwcc is an HTTP cookie associated with Google Ads advertising services. It appears on a website when that site uses Google Ads conversion tags, remarketing tags, or other Google advertising scripts (for example via Google Tag Manager or gtag.js).
It is set by Google domains (typically related to google.com or its subdomains) when the advertising script loads and executes on the page — not necessarily on the first visit if the script is blocked by a consent management platform.
What data it stores
The cookie mainly stores an identifier tied to a browsing session or ad interaction, used to link an ad view or click to a later conversion on the site. The exact value format is not publicly documented in detail by Google and may vary.
Data collected through gwcc is sent to Google's servers, where it is processed for conversion reporting and bid optimization within Google Ads campaigns.
What it is used for
For Google, gwcc helps measure advertising campaign effectiveness by attributing a conversion (purchase, form submission, call) to a specific ad or click.
For the website owner, this cookie underlies conversion reporting in Google Ads and automated bidding optimization, helping evaluate the return on paid advertising campaigns.
Does it require consent?
gwcc is classified as a marketing/advertising cookie. Under the GDPR (Regulation 2016/679) and the ePrivacy Directive, this type of cookie cannot be placed before the visitor gives explicit consent.
- The site owner must list the cookie in the cookie policy under the „marketing” category.
- The Google Ads script must be technically blocked until consent is obtained, not merely hidden.
- Consent must be as easy to withdraw as it was to give.
How to block or delete gwcc
A visitor can delete or block gwcc from browser settings (Chrome, Firefox, Edge, Safari) under per-site cookie management, or use ad-tracking blocking extensions.
For site owners, blocking must happen technically, before consent is given. A CMP such as CookieFix can automatically prevent Google Ads scripts (including those setting gwcc) from loading until the visitor accepts the „marketing” category, avoiding non-compliant placement of the cookie.
Frequently asked questions
It is a marketing cookie set by Google Ads, used to track ad interactions and report conversions for advertising campaigns.
It typically lasts around 3 months, though this can vary depending on the campaign setup and Google script used.
Yes, since it is a marketing/tracking cookie, it requires prior consent under GDPR and the ePrivacy Directive before being placed.
The Google Ads script that sets gwcc must be technically blocked until consent is given, for example through a CMP like CookieFix that controls the loading of marketing scripts.