This paper examines the security concerns surrounding Radio Frequency Identification (RFID) and compares different security methodologies to ensure data privacy. After analyzing lightweight cryptographic algorithms, the Klein algorithm was chosen for its low power consumption. We evaluate potential security threats and attacks in three scenarios, namely storing the key in a tag, database, and as user input, and also demonstrate the integration of the Klein algorithm through software simulation. We conclude that lightweight cryptography is the best method to ensure the security of RFID systems.