Embodiments include circuits, apparatuses, and systems for voltage level shifter monitors. In embodiments, a voltage level shifter monitor may include a first signal generator to generate a signal in a first voltage domain, a second signal generator to generate a second signal in a second voltage domain, where the second digital signal corresponds to the first digital signal, a voltage level shifter replica circuit to convert the first digital signal from the first voltage domain to a third digital signal in the second voltage domain, and a comparison circuit to generate a digital error signal based at least in part on the second digital signal and the third digital signal. Other embodiments may be described and claimed.