The disclosure is directed to garbage cleaning of cookies in a web browser. A computer-implemented process according to embodiments includes: determining a presence of a first cookie and a second cookie in the web browser, the first cookie and the second cookie representing a cleanliness status of the web browser; in response to determining that the first cookie and the second cookie are both present in the web browser, indicating a status of the web browser as clean and taking no further cleaning action; and in response to determining that only the first cookie is present in the web browser, indicating the status of the web browser as needs cleaning, and performing garbage collection of cookies in the web browser.