Frances Hamilton Arnold was born in Pittsburgh, Pennsylvania, to William Howard Arnold, a nuclear physicist, and Josephine Inman Arnold. Her early life was marked by a strong interest in science and exploration.

Arnold demonstrated a rebellious streak, hitchhiking across Europe and working odd jobs to finance her travels. This period instilled in her a sense of independence, resourcefulness, and a global perspective.

Arnold graduated from Princeton University with a Bachelor of Science degree in Mechanical and Aerospace Engineering. This foundational education provided her with a strong understanding of engineering principles and problem-solving techniques.

After graduating from Princeton University, Arnold worked for the Solar Energy Research Institute (now the National Renewable Energy Laboratory) analyzing energy policy and performing solar energy research. This experience exposed her to the challenges and opportunities in renewable energy and sustainable technologies.

Arnold earned her Ph.D. in Chemical Engineering from the University of California, Berkeley. Her doctoral research focused on developing techniques for protein engineering, laying the groundwork for her future innovations in directed evolution.