Delete Evercookie, the un-deletable cookie with Anonymizer Nevercookie or BleachBit

There is a new kind of Cookie in town. One that is almost impossible to delete. It stores itself in multiple places and if found, can be rebuilt and stored in all the places again. EverCookie is an open source JavaScript API available, that produces extremely persistent cookies in a browser. Its goal is to identify a client even after they’ve removed standard cookies, Flash cookies (Local Shared Objects or LSOs), and others.

What is Evercookie

Evercookie accomplishes this by storing the cookie data in several types of storage mechanisms that are available on the local browser. Additionally, if evercookie has found that the user has removed any of the types of cookies in question, it recreates them using each mechanism available.

Specifically, when creating a new cookie, it uses the following storage mechanisms when available:

  • Standard HTTP Cookies
  • Local Shared Objects (Flash Cookies)
  • Silverlight Isolated Storage
  • Storing cookies in RGB values of auto-generated, force-cached PNGs using HTML5 Canvas tag to read pixels (cookies) back out
  • Storing cookies in Web History
  • Storing cookies in HTTP ETags
  • Storing cookies in Web cache
  • caching
  • Internet Explorer userData storage
  • HTML5 Session Storage
  • HTML5 Local Storage
  • HTML5 Global Storage
  • HTML5 Database Storage via SQLite

Remove or delete EverCookies

BleachBit is a cleaner which claims to deletes evercookies. It supports Internet Explorer, Firefox, Chrome, Opera, Safari and also works and Windows & Linux platforms.

Firefox users can also try Anonymizer Nevercookie, a free Firefox plugin that protects against the Evercookie API.

Now read: What information is available about you on the internet when online.

Posted by on , in Category Security with Tags
Anand Khanse is the Admin of, a 10-year Microsoft MVP Awardee in Windows (2006-16) & a Windows Insider MVP. Please read the entire post & the comments first, create a System Restore Point before making any changes to your system & be careful about any 3rd-party offers while installing freeware.


  1. The latest BleachBit 0.8.7 (non-beta) cleans evercookies too! 🙂

    (I am the author of BleachBit)

  2. ^ Thanks for the clarification, Andrew 🙂

  3. Marcus

    So how do you know if this cookie actually exists within your own computer? usually I’m pretty clued up on this stuff but not with checking for cookies.

  4. Well, I guess the only way to be safe, is to clear out all your cookies periodically.

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