While there is no official "time limit" for transiting through Changi Airport, most airline transit facilities and the 96-hour Visa Free Transit Facility (VFTF) imply a maximum stay of 4 days for eligible travelers. For a standard layover, Changi is designed to keep you entertained for 5 to 24 hours. If your layover is between 5.5 and 24 hours, you can even register for a Free Singapore Tour. Many travelers choose to spend an entire day (12–15 hours) just exploring the Jewel (the waterfall), the butterfly gardens, and the cinemas. However, if you are staying airside (inside the transit area) without clearing immigration, most lounges and "transit hotels" operate on 6-hour or 12-hour bookings, so you would need to manage your sleep and comfort accordingly for very long stays.