As of my knowledge cutoff in September 2021, the Women's Pound-for-Pound (P4P) rankings were not as widely recognized or consistently updated compared to the men's P4P rankings. However, there were a few standout women boxers who were widely regarded as among the best pound-for-pound fighters. Here are a few notable women boxers as of September 2021:


Claressa Shields: Claressa Shields, a multiple-time Olympic gold medalist, has achieved remarkable success in both amateur and professional boxing. She has won multiple world titles in different weight classes and was considered one of the best pound-for-pound female boxers at the time.


Katie Taylor: Katie Taylor, an Irish boxer, has made a significant impact in women's boxing. She has unified multiple world titles in the lightweight division and has consistently been ranked among the best female boxers in the world.


Amanda Serrano: Amanda Serrano, a Puerto Rican professional boxer, has captured world titles in multiple weight divisions. Known for her exceptional punching power, she has been recognized as one of the top women's boxers in recent years.


It's important to note that the landscape of women's boxing is continuously evolving, and new talents emerge as the sport gains more attention and recognition. For the most up-to-date information on the current best pound-for-pound women's boxer, it is recommended to consult reputable boxing organizations, rankings, or publications that specialize in women's boxing.