You can find several free APIs for your travel affiliate website that enhance functionality. FlightsLogic offers a customizable free travel API that provides real-time availability for flights, hotels, and car rentals. You can integrate this API easily into your platform to improve user experience. Skyscanner also provides a free travel API, allowing you to access competitive airfares and global content from numerous suppliers. Kayak offers a free API that helps you compare prices for flights, hotels, and car rentals. These APIs streamline the booking process and provide valuable data for your users, making them excellent choices for your affiliate website.