The cf_clearance cookie is a special cookie used by Cloudflare as proof that a visitor has successfully passed a security check (a challenge).

When Cloudflare protects a website (to guard against bots, attacks, or suspicious traffic), it may present challenges (like JavaScript challenges, CAPTCHA, firewall checks). Once you, the visitor, pass that challenge, Cloudflare issues you a cf_clearance cookie.

This tells the site that you are a valid human visitor (or at least passed the checks), so you don’t have to do more challenges while the cookie is valid.

Why It Matters / Use in Blocking & Fingerprinting Logic

• Bypasses repeated challenges: With cf_clearance, you don’t have to solve the same challenge over again on each page of the site, as long as it hasn’t expired.
• Security level tracking: Some pages may require a higher clearance level than others. If you had a lower clearance before, you might still need to solve a more demanding challenge to get a stronger cf_clearance cookie.
• Part of Cloudflare’s bot protection stack: It’s used alongside other cookies (like __cf_bm) to manage traffic and differentiate human vs automated visitors.
• Limits & scope: It is tied to your session, user agent, and IP address. Changing any of those may invalidate or lose privilege from the cookie.

Simple Example in Context

1. You visit a Cloudflare-protected site.
2. The site shows a security challenge (e.g. a hidden JavaScript check or CAPTCHA).
3. You pass that check.
4. Cloudflare gives you a cf_clearance cookie in your browser.
5. As long as that cookie is valid and you stay on the same IP and user agent, you won’t be challenged again on other pages.

In Short: The cf_clearance cookie is Cloudflare’s way of saying:
“Yes – you passed the challenge. Let you in.”

It helps reduce repeated block checks, but it’s tied to your session, IP, and browser identity, so changing those can cause the cookie to stop working.

How Kameleo Helps

The Kameleo browser “pretends” to be human so that when Cloudflare asks you to prove you’re not a bot, Kameleo can pass the test.

Once it passes, Cloudflare gives the browser a cf_clearance cookie – essentially a permission slip. Kameleo then reuses that cookie in subsequent requests so that Cloudflare stops challenging you again.