What is the average heart rate after a run?

The answer is dependent on how strenuous the run was, your age and physical condition, and how long after the run the pulse is taken.

A 40 year old in moderate condition might reasonably work up a heart rate of about 140 on a run. That heart rate will decrease in the few minutes after the run but how quickly the decrease occurs depends on the individual.

When a runner really overdoes the exercise, the heart rate may stay above 100 for quite a long time (10 minutes to an hour) after the run.

Someone in great physical shape will have their heart rate almost back to the resting level in just a few minutes following a moderate run.