It is a strangely controversial topic but I'll give you my two cents.
Unfortunately, like so many things with the coronavirus there are conflicting reports and imperfect information. For example, data from Iceland and a small village in Italy that tested its entire population suggest that most cases are asymptomatic or have only mild or moderate symptoms. Other studies suggest that asymptomatic cases are not as widespread. Many scientists have called for random testing to try to get a better handle on it. Those efforts have started but so far have not yielded much useful information.
You will hear from a handful of people on this forum who have no expertise on this issue, but think they know more than the epidemiologists who are studying these questions.
Overcoming confirmation bias during COVID-19
Edit: On this topic, and hot off the presses, is this report from Italy:
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Note: I seriously doubt this data is representative, but is more anecdotal evidence of asymptomatic infections