Evercookie Test
This tool checks cookieData, localData, and sessionData storages for cookies that are resistant to deletion.
UID = NOT SET
Click the button to create an evercookie. Your anonymity will not be compromised: a cookie is a random number between 1 and 1000 that we use to test evercookies. We do not track you using it.
userData
cookieData
localData
globalData
sessionData
windowData
pngData
etagData
cacheData
lsoData
dbData
slData
FAQ
How can I detect the presence of evercookies in my browser?
What data can an Evercookie collect?
Does Evercookie detection mean my data has been compromised?
Can the tool delete Evercookies after detecting them?
How can I protect against Evercookies?
This tool is designed to check for the presence of evercookies—specific types of persistent tracking cookies that are difficult to remove due to their ability to regenerate after standard deletion. These cookies can be stored in various locations on a user's device, including localStorage, sessionStorage, and even in the image cache.
How evercookie detection technology works
The tool scans not only standard cookies but also localStorage, sessionStorage, IndexedDB, and other browser APIs that can be used to save data. The checking process consists of several stages:
- First, the tool creates entries in all available storage locations, then attempts to delete them.
- After the deletion attempt, the tool checks each storage again to determine if the data has been restored.
- The user is provided with a report that shows which data was restored and in which storage, giving an understanding of the resilience of evercookies.
This approach allows users and developers to assess how effectively their current privacy protection methods are able to handle the removal of persistent tracking cookies.