Depending on what type of user depends on what type of license to buy.
A dongle is a small security device that plugs into your computer. It acts like a mobile serial number for FlowJo, allowing users to run FlowJo on any number of computers (one at a time).
A license number will run FlowJo on one, and only one, computer. It is a good option for labs and users who don’t want to worry about losing a dongle (or getting it stolen) or who only have one workstation they will be using for analysis.
If you start with a serial number and your lab expands with more computers you can convert a serial number into a dongle for a small fee of $300 plus shipping.
Large institutions with numerous users typically have serial numbers tied to a site license. This is the ideal licensing method and the cheapest.