Abstract Motivation: Nanopore sequencers allow sequencing data to be accessed in real-time. This allows live analysis to be performed, while the sequencing is running, reducing the turnaround time of the results. We introduce realfreq, a framework for obtaining real-time base modification frequencies while a nanopore sequencer is in operation. Results: Realfreq calculates and allows access to the real-time base modification frequency results while the sequencer is running.