What are the limits for visa exempt entries into Thailand for Singapore passport holders?

Singapore passport holders have theoretically no limit on visa exempt entries by air, but there is a practical limitation with potential scrutiny from immigration officers after multiple entries. Specifically, while no official cap exists, frequent back-to-back entries may invite questioning, especially if staying the maximum duration allowed each time. In contrast, when entering by land, entries are limited to two per year. Some users have reported being advised to apply for a TR visa after several air entries.