One of the key relationships in radar is the relationship between time and range.  Frequency is simply the reciprocal of time.  In a radar, pulses always travel at the speed of light c.  The time it takes a pulse to travel to a target and back is, in formula form

t = 2R/c.

This is really quite a remarkable formula.  The time, range, and frequency components can be interpreted in several different ways.  The radar range, time, and frequency calculator shows you three consistent ways to interpret the relationship between the variables.  Select a meaning from the popup menus in the first column to find out the meaning.  The first meaning is that range is the range to a target and time is how long it takes a pulse to get to the target and back.  The second meaning is the relationship between unambiguous range, pulse repetition interval (time between transmit pulses), and pulse repetition frequency.  The third meaning is the relationship between the range bin width , the corresponding transmit pulse width, and the receiver bandwidth (assuming a matched filter design).  You can enter any variable you choose.  The calculator will determine the proper value and select reasonable units for engineering notation. When you enter data, be certain that you use the proper units from the popup units menus.