Update and Delete Calendar Events

Once a calendar event is created, you can update its title, time, description, location, and other properties at any time using Apps Script. You can also delete events — individually or in bulk — based on title, date range, or any other criteria.

Updating an Event by ID

The most reliable way to update a specific event is by its ID:

function updateEventById() {
  var eventId = "YOUR_EVENT_ID";
  var calendar = CalendarApp.getDefaultCalendar();
  var event = calendar.getEventById(eventId);

  event.setTitle("Rescheduled Follow-up – Mark Chen (Enterprise Plan)");
  event.setDescription("Rescheduled at customer request. New time confirmed via email.");

  // Reschedule to the next day
  var newStart = new Date(event.getStartTime().getTime() + 24 * 60 * 60 * 1000);
  var newEnd = new Date(event.getEndTime().getTime() + 24 * 60 * 60 * 1000);
  event.setTime(newStart, newEnd);

  Logger.log("Event updated: " + event.getTitle());
}

Updating Events Matching a Search Term

This reschedules all follow-up calls that contain a customer name:

function rescheduleCustomerFollowUp() {
  var calendar = CalendarApp.getDefaultCalendar();
  var now = new Date();
  var nextMonth = new Date();
  nextMonth.setMonth(nextMonth.getMonth() + 1);

  var events = calendar.getEvents(now, nextMonth, { search: "Mark Chen" });

  events.forEach(function(event) {
    // Push each matching event forward by 3 days
    var newStart = new Date(event.getStartTime().getTime() + 3 * 24 * 60 * 60 * 1000);
    var newEnd = new Date(event.getEndTime().getTime() + 3 * 24 * 60 * 60 * 1000);
    event.setTime(newStart, newEnd);
    Logger.log("Rescheduled: " + event.getTitle() + " → " + newStart);
  });
}

Updating Event Status When a Deal Closes

When a deal is marked Closed in the Sales Tracker, update the corresponding follow-up event title to reflect this:

function markFollowUpsAsClosed() {
  var sheet = SpreadsheetApp
    .getActiveSpreadsheet()
    .getSheetByName("Sales Tracker");

  var data = sheet.getRange(2, 1, sheet.getLastRow() - 1, 7).getValues();
  // Columns: [Customer Name, Email, Product, Amount, Region, Sales Rep, Status]

  var calendar = CalendarApp.getDefaultCalendar();
  var now = new Date();
  var nextMonth = new Date();
  nextMonth.setMonth(nextMonth.getMonth() + 1);

  data.forEach(function(row) {
    var customerName = row[0];
    var status = row[6];

    if (status !== "Closed") return;

    var events = calendar.getEvents(now, nextMonth, { search: customerName });
    events.forEach(function(event) {
      if (event.getTitle().indexOf("Follow-up") !== -1) {
        event.setTitle("[CLOSED] " + event.getTitle());
        event.setColor(CalendarApp.EventColor.GREEN);
        Logger.log("Updated event for closed deal: " + customerName);
      }
    });
  });
}

Deleting a Specific Event

function deleteEventById() {
  var eventId = "YOUR_EVENT_ID";
  var calendar = CalendarApp.getDefaultCalendar();
  var event = calendar.getEventById(eventId);

  if (event) {
    event.deleteEvent();
    Logger.log("Event deleted.");
  } else {
    Logger.log("Event not found.");
  }
}

Deleting All Events Matching a Search

This cancels all follow-up events for a specific customer — useful when a deal is lost:

function cancelFollowUpsForCustomer(customerName) {
  var calendar = CalendarApp.getDefaultCalendar();
  var now = new Date();
  var nextMonth = new Date();
  nextMonth.setMonth(nextMonth.getMonth() + 1);

  var events = calendar.getEvents(now, nextMonth, { search: customerName });

  events.forEach(function(event) {
    event.deleteEvent();
    Logger.log("Deleted: " + event.getTitle());
  });
}

// Example usage
cancelFollowUpsForCustomer("Mark Chen");

Available Event Color Constants

CalendarApp.EventColor.PALE_BLUE    // Light blue
CalendarApp.EventColor.PALE_GREEN   // Light green
CalendarApp.EventColor.MAUVE        // Purple
CalendarApp.EventColor.PALE_RED     // Red
CalendarApp.EventColor.YELLOW       // Yellow
CalendarApp.EventColor.ORANGE       // Orange
CalendarApp.EventColor.CYAN         // Teal
CalendarApp.EventColor.GRAY         // Gray
CalendarApp.EventColor.BLUE         // Blue
CalendarApp.EventColor.GREEN        // Green
CalendarApp.EventColor.RED          // Red