TCF Compliance Checker

A TC String (Transparency and Consent String) is a base64-encoded string defined by the IAB Transparency and Consent Framework (TCF). It encodes a user's consent choices — which purposes and vendors they have approved — so that ad tech vendors can read and respect those preferences.

TCF 2.3 introduced policy version 5 and made the DisclosedVendors segment mandatory. TC Strings using TCF 2.2 (policy version 4) became invalid after February 28, 2026. All CMPs must now include a DisclosedVendors segment listing every vendor shown in the consent UI.

Look for cookies named "euconsent-v2" or "eupubconsent-v2" in your browser's developer tools (Application > Cookies). You can also call window.__tcfapi('getTCData', 2, callback) in the browser console if a TCF-compliant CMP is present on the page.

A CMP ID of 0 means the consent management platform is not registered with the IAB. Production CMPs must obtain a valid CMP ID from the IAB to be TCF-compliant. A CMP ID of 0 is typically used during development or testing.

Yes, completely free with no sign-up required. You can decode and validate TC Strings or scan websites to find and check their TCF consent strings.