There is always a possibility of errors to happen into the system when we transmit data over a data link or a network which may affect the integrity of the system leading into a compromised transmission, according to this The performance of the system can be estimated by bit error rate AS (BER)provides an ideal way to achieved such transmission. In this paper we present a graphical user interface (GUI) design of the OSI Physical layer in order to calculate the BER (bit error ratio) of three different modulators (QPSK,16QAM And 64QAM) Each modulator will individually work to achieve results in simulation with respect to the (SNR) signal to noise ratio. We will show a clean figures of the process when simulation is running and comparison of the modulators. Previous researches of (BER) have shown that there are different ways to calculate the BER in order to ensure the quality of digital transmission system.