How many dreams does the average person have in one night?
The number of dreams can vary greatly and are different for each individual on any given night. Many variables play into this such as the total length or duration of your sleep, whether or not your sleep was disturbed or interrupted during REM stage sleep etc. (REM is the stage during which we are thought to dream).
REM makes up 20-25% of overall sleep architecture in adults and you should cycle through REM at least a couple of times per night. REM stages typically last anywhere from 90-120 minutes each. It is thought that we typically have between 3-5 dreams per night, based on an 8hr sleep. However it is not uncommon to have up to 7 or possibly more if you have been severely sleep restricted.
It is now believed that we dream in Non-REM Sleep as well as during REM sleep, which would increase the count. Most people, however, are unaware of these dreams unless participating in a sturdy designed to find them. Some people are aware of them but even for us they tend to fade quickly. Here is a link to a psychology today article on the subject. (Sorry the site won’t allow ‘links’ till i earn votes and it won’t let me paste link into body. Not a sensible rule to me).
Alexis Campbell absolutely correct that there is a wide variance among individuals. Many things can impact the amount, quality and how much people remember of their dreams including health issues and medications. But we can influence both quantity and quality of dreams remembered.