Systems, methods and media for detecting Nagling on a TCP network connection are disclosed. Embodiments may generally include a system with a Nagle detection threshold determiner for determining a Nagle detection threshold based on the network connection. The system may also generally include a Nagle detection module in communication with the Nagle detection threshold determiner for observing a small segment at a second time following an acknowledgement indicative of a Nagling condition at a first time, wherein the Nagle detection module also may detect a Nagling condition if the difference between the second time and the first time is less than or equal to the Nagle detection threshold. The system may be a receiver computer or a network computer. The system may also generate and transmit a notification of the Nagling condition, increment a Nagle monitor counter, or save an indication of the Nagling condition in a log.