Purpose: The aim of this study is to develop a flexible simulation software (QS-Sim Tool) that can simulate queuing system models for the service sector, measure performance and perform workforce optimization. Theory and Methods: With the developed software, a service or production system can be modeled. New parallel stations can be added to the system, and customer arrival and service distributions can be determined as Poisson, Exponential, Normal, Erlang distributions or deterministic according to the model (Figure A). With the software, the performance for the queuing problems encountered in the service sector can be measured and the costs of different personnel numbers can be obtained in the optimization interface. Results: In this study, different types of examples of queuing problems encountered in the service sector are given and simulated in the developed software. Within the scope of this study, a model for four queuing systems for different sectors has been created and simulated. Conclusion: Performances of queuing systems with the help of software; The probability of the system being idle (P0), the number of people waiting in the queue (Lq ) and the service (Ls), the waiting times in the queue (Wq ) and the service (Ws) together with the longest waiting times in the queue (Max Wq ) and the service (Max Ws ), the idle waiting time of the personnel, the overtime hours and the number of people leaving the system without receiving service can also be calculated.