A command that becomes available in the Query submenu if you select a sound-analysis object that is a function of time and that is evenly sampled in time (Pitch, Formant, Intensity, Harmonicity).

The Info window will tell you the time difference between consecutive frames, e.g. the time difference between consecutive formant circles in the sound editor window.

Details for hackers

If you select one of the above objects and click Inspect, you can see how the time step is stored in the object: it is the dx attribute.