What is chart vacancy?

Chart vacancy refers to the number of vacant seats or empty berths that become visible after the IRCTC reservation chart is prepared. The chart is typically prepared about four hours before the train departs. Once the chart is finalised, all unbooked berths, cancellations from confirmed passengers, and unused quota seats are displayed as vacant. This allows passengers who did not get confirmed tickets earlier to check for last-minute availability and travel. Chart vacancy is especially useful for waitlisted passengers or those who need to travel urgently and want to know if any berths are still free.