Methods and systems for recommending an optimal subnet for assignment are disclosed. In some embodiments, the methods include the following: receiving a request for assignment of a subnet, the request including request data; accessing a subnet database to review a current register of subnets; querying the current register of subnets to determine a size of each of the available subnets and a number of available subnets positioned numerically before and after each of the available subnets thereby generating subnet availability data; applying predetermined subnet recommendation rules to both the request data and the subnet availability data to determine a recommended subnet for assignment; updating the current register to indicate that the recommended subnet for assignment is unavailable; presenting the recommended subnet; confirming assignment of the recommended subnet; and if assignment of the recommended subnet is not confirmed, updating the current register to indicate that the recommended subnet is available.