In a decoder, the BER is calculated during a decode operation of the decoder. Access to decoder components for obtaining signal data for use in calculating the BER is provided during the decode operation when the components are not used by the decoder. A fetch component serves to provide the input signal to both the decoder and BER calculator at the same time. The BER calculator calculates the BER based on the output from the previous iteration. Since the decoder keep decoding the data until the final two iterations result in the same output, the calculation of the BER can be performed during the last iteration of the decoding process. An HDA early termination signal is used to confirm an accurate BER calculation.