I was ages searching for a solution to this. I wanted to have a link on an intranet to a user’s own Delve profile in SharePoint Online. Delve is Microsofts ‘personal search and discovery tool.
This is the URL you can use.
https://yourcompanyname-my.sharepoint.com/person.aspx is another option. Thanks to Coxy on Twitter for that.
By the way here is a useful admin guide to Delve. Well worth reading.