<p>Bounties last one week, so you can get a decent approximation by counting back from when it says it will expire.  If you need a more precise time, click the edit history link (at bottom center), and one of the noted events will be when the bounty was started and by whom.  </p>

<p><a href="https://i.stack.imgur.com/wmbuv.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/wmbuv.png" alt="enter image description here"></a></p>
