How to fix slow update speed on Kali Linux ? Not only you but most people face this problem after installing Kali Linux. Though the solution is much simpler than you think. You just have to update your mirrors in Kali Linux Open terminal and type sudo nano /etc/apt/sources.list You can use any text editor you want (like vim) After this your sources.list file will open deb https://mirrors.ocf.berkeley.edu/kali kali-rolling main non-free contrib deb-src https://mirrors.ocf.berkeley.edu/kali kali-rolling main non-free contrib Just add above two lines. Delete any previous sources (if exist) otherwise you will get duplicate sources error when you will run update command next time.