  One of the fundamental tasks in quantum information processing is to measure
the quantum channels. Similar to measurements of quantum states, measurements
of quantum channels are inherently stochastic, that is, quantum theory provides
a formula to calculate the probability of obtaining an outcome. The upper bound
on each probability associated with the measurement outcome of the quantum
channels is a fundamental and important quantity. In this study, we derived the
upper bounds of the probability in a channel measurement for specific classes
of quantum channels. We also present two applications for the upper bounds. The
first is the notion of convertibility considered by Alberti and Uhlmann and the
second is the detection problem of a quantum channel. These applications
demonstrate the significance of the obtained upper bounds.
