They’re two different things, so there’s no conversion — and no need for one. A recording is the record of a hike you did (and recordings are what count towards your stats). “Completed hikes” is a checklist for ticking off official or planned HiiKER hikes — open a hike and tap the checkmark to mark it done. On the website, you can open a recording and use “Copy to hikes” to create a planned hike from its track if you want to re-walk or share the route.