OneTaskBy Tim King · Updated
Cookie Consent Checker
Find Analytics and Ad Cookies Set Before a Visitor Accepts Your Banner
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How the Cookie Consent Checker works
This cookie consent checker sorts the cookies on your site into those that are strictly necessary and those that need a visitor's consent. Paste what your browser shows before anyone clicks the banner, or after they reject all, and it flags every analytics or advertising cookie that should not be there yet.
How the cookie consent checker works
Under GDPR, UK GDPR and the ePrivacy rules, a site may only set cookies without asking when they are strictly necessary, such as a session, a shopping basket or a load balancer. Analytics, advertising and most functional cookies need consent first, and must stay off if the visitor rejects them. A common failure is a banner that looks right while Google Analytics or a Meta pixel loads straight away.
To capture your cookies, open the site in a private window, open developer tools, and copy the cookie table from the Application or Storage tab. You can also paste document.cookie output or Set-Cookie headers. The checker recognises common cookies from Google, Meta, Microsoft, HubSpot, Hotjar, consent tools and popular platforms, and labels the rest as unknown.
Each cookie gets a category, whether it needs consent and any findings. Consent cookies that last more than 13 months are flagged, as regulators such as the CNIL expect. SameSite=None without Secure and missing Secure flags are flagged too.
FAQ
How do I copy cookies from Chrome?
Open developer tools, choose the Application tab, then Cookies and your site. Select the rows in the table, copy them and paste them here. The tab-separated columns are read, including expiry and flags.
Is Google Analytics strictly necessary?
No. Analytics cookies such as _ga measure visits rather than making the site work, so in the EU and UK they need consent first. Some privacy-focused analytics set no cookies at all, which avoids the issue.
What does an unknown cookie mean?
The checker does not recognise the name. Search for it, or find the script that sets it, then decide if it is necessary. Unknown cookies set before consent are a common source of complaints.
Is this legal advice?
No. It is a technical check based on common interpretations of the rules. Your lawyer or data protection officer should confirm how your cookies are classified and what your banner needs to show.
See also: all Security & Identifiers tools, Dev Utilities, Formatters & Validators, Data & Encoding, SEO, Accessibility, AI.
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