diff --git a/soitool/database.py b/soitool/database.py
index 8212ed60d7fae79014f1d2b5d718fd94d6770bab..d3123c39f3af4d2e7569d44758ab125788217803 100644
--- a/soitool/database.py
+++ b/soitool/database.py
@@ -205,22 +205,24 @@ class Database:
 
     def seconds_to_next_update(self):
         """
-        Rerturns time to next updated of Codebook in seconds.
+        Rerturns time to next update of Codebook in seconds.
 
         Returns
         -------
-        time_diff : float
+        seconds_to_update : float
             Time to next update in seconds
         """
         stmt = "SELECT Timestamp FROM LastUpdated"
         last_updated = self.conn.execute(stmt).fetchall()[0][0]
         # Convert datetime string to datetime object
         last_updated = datetime.strptime(last_updated, "%Y-%m-%d %H:%M:%S.%f")
-        date_and_time_now = datetime.now()
-        time_diff = date_and_time_now - last_updated
-        # Time difference in seconds
-        time_diff = time_diff.total_seconds()
-        return time_diff
+        # 24h in seconds minus the difference of the last update time and
+        # current time in seconds makes the current number of seconds
+        # til next update.
+        seconds_to_update = (24 * 60 * 60) - (
+            datetime.now() - last_updated
+        ).total_seconds()
+        return seconds_to_update
 
     def add_code_to(self, word, mode="ascii"):
         """