A PNR (Passenger Name Record) is a six-character alphanumeric code that serves as your digital "file" in an airline's database, and the best way to verify its validity is through the airline's official website or mobile app. Navigate to the "Manage Booking" or "My Trips" section and enter your PNR along with your last name. If the PNR is valid, the system will display your full itinerary, ticket number, and flight status. It is important to look for the "Ticketed" or "Confirmed" status; sometimes a PNR is created during a reservation, but if the payment wasn't finalized, the record will eventually be purged. If you booked through a third-party site (like Expedia or Skyscanner), they often provide their own internal "Reference Number," which is different from the airline's PNR. You should ensure you have the carrier-specific code to check directly with the airline. You can also use independent tools like CheckMyTrip or ViewTrip (depending on the Global Distribution System used) to verify the details. If your flight details do not appear or if you receive an error message, you should contact the airline immediately to ensure your seat hasn't been canceled.