Koh Phi Phi tends to be quite safe for solo female travelers. As with any location, it's critically important to take normal safety precautions and stay aware of your surroundings. The locals are typically friendly and hospitable, and the island is visited by many travelers which creates a rather safe environment. Though, occasional petty theft or tourist scams have been reported, so it's recommended to secure your belongings. Furthermore, it's vital to respect local customs and rules. Nighttime safety can vary based on area, and it is advisable to avoid isolated areas and keep to well-lit, populated places.