To calculate how many seconds until 12:00 PM (noon) today, I need to know the current time. Since it is currently 5:39 PM (17:39) UTC on August 22, 2025, the time for 12:00 PM today has already passed. If you want to know how many seconds until 12:00 PM tomorrow, I can calculate that for you. Please confirm if you want the seconds until noon tomorrow or some other time.