diff --git a/scripts/delete-unused-users.py b/scripts/delete-unused-users.py
index 15f46faff..f5285d311 100755
--- a/scripts/delete-unused-users.py
+++ b/scripts/delete-unused-users.py
@@ -22,7 +22,6 @@
 import sys
 
 from dateutil.parser import parse
-from jhub_client.api import JupyterHubAPI
 
 logging.basicConfig(stream=sys.stdout, level=logging.WARNING)
 logger = logging.getLogger(__name__)
@@ -33,7 +32,27 @@
     "Authorization": f"Bearer {token}",
 }
 
-def retrieve_users(hub_url):
+def parse_timedelta(args):
+    """
+    Parse timedelta value from literal string constructor values
+
+    Trying to support all possible values like described in
+    https://docs.python.org/3/library/datetime.html#datetime.timedelta
+    """
+    result = {}
+    for arg in args.split(','):
+        key, value = arg.split('=')
+        try:
+            value = int(value)
+        except ValueError:
+            try:
+                value = float(value)
+            except ValueError as e:
+                raise argparse.ArgumentError from e
+        result[key] = value
+    return timedelta(**result)
+
+def retrieve_users(hub_url, inactive_since):
     """Returns generator of user models that should be deleted"""
     url = hub_url.rstrip("/") + "/hub/api/users"
     next_page = True
@@ -46,7 +65,7 @@ def retrieve_users(hub_url):
         user_list = resp["items"]
         for user in user_list:
             # only yield users that should be deleted
-            if should_delete(user):
+            if should_delete(user, inactive_since):
                 yield user
 
         pagination = resp["_pagination"]
@@ -57,10 +76,10 @@ def retrieve_users(hub_url):
                 "limit": next_page["limit"],
             }
 
-def should_delete(user):
+def should_delete(user, inactive_since):
     """
     Returns a boolean if user is to be deleted.  The critera are:
-      - was the user active in the past 24 hours?
+      - was the user active in the past inactive_since period?
       - is there a current user server running?
     """
     last_activity_str = user.get('last_activity', False)
@@ -71,16 +90,16 @@ def should_delete(user):
             logger.error(f"Unexpected value for user['last_activity']: {user['last_activity']}")
             raise
         if isinstance(last_activity, datetime):
-            was_active_last_day = datetime.now().astimezone() - last_activity < timedelta(hours=24)
+            was_active_recently = datetime.now().astimezone() - last_activity < inactive_since
         else:
             logger.error(f"For user {user['name']}, expected datetime.datetime class for last_activity but got {type(last_activity)} instead.")
             raise
 
         logger.debug(f"User: {user['name']}")
         logger.debug(f"Last login: {last_activity}")
-        logger.debug(f"24hrs since last login: {was_active_last_day}")
+        logger.debug(f"Recent activity: {was_active_recently}")
         logger.debug(f"Running server: {user['server']}")
-        if was_active_last_day or user['server'] is not None:
+        if was_active_recently or user['server'] is not None:
             logger.info(f"Not deleting {user['name']}")
             return False
         else:
@@ -101,7 +120,7 @@ def main(args):
     and if so, delete them!
     """
     count = 1
-    for user in list(retrieve_users(args.hub_url)):
+    for user in list(retrieve_users(args.hub_url, args.inactive_since)):
         print(f"{count}: deleting {user['name']}")
         count += 1
         if not args.dry_run:
@@ -115,7 +134,7 @@ def main(args):
 if __name__ == "__main__":
     argparser = argparse.ArgumentParser()
     argparser.add_argument(
-        '-h',
+        '-H',
         '--hub_url',
         help='Fully qualified URL to the JupyterHub',
         required=True
@@ -125,6 +144,13 @@ def main(args):
         action='store_true',
         help='Dry run without deleting users'
     )
+    argparser.add_argument(
+        '--inactive_since',
+        default='hours=24',
+        type=parse_timedelta,
+        help='Period of inactivity after which users are considered for deletion (literal string constructor values for timedelta objects)'
+        # https://docs.python.org/3/library/datetime.html#timedelta-objects
+    )
     argparser.add_argument(
         '-v',
         '--verbose',
@@ -145,5 +171,6 @@ def main(args):
         logger.setLevel(logging.INFO)
     elif args.debug:
         logger.setLevel(logging.DEBUG)
+    logger.debug(args)
 
     main(args)