If you need your visitors to pick a date in a form, use the calendar widgets. This makes it easier to locate the right date, and reduces the risk of errors considerably. You can use formulas to calculate a default date. 

Calendar widget

Calendar widgets make it much easier for the user to pick the right date. It also makes it easier to count from one date to another. The widgets ensure that any date picked from the calendar is valid, and formats it correctly for the recipient of the electronic web form using the regional settings.

Screenshot of an example of the Calendar widget

The calendar automatically uses the developer’s regional settings for the names of months and days. If your regional settings are for Swedish, your calendar looks like this instead:

Screenshot of a calendar when the developer has Swedish regional settings

You may need to change your regional settings before you convert the spreadsheet to a web page. Example: If you normally use the regional settings for French (Canada), but the web form you are developing is in English (Canada), you must switch to the corresponding regional settings before the conversion and you may also have to restart Excel.

When the user selects a date in the calendar, it appears in the widget cell, formatted according to your computer’s regional settings. The calendar may be positioned at a default date, e.g. today + 30 days. If there is a default date, it is visible in the date field already from the start.

Excel serial numbers

Excel stores dates as sequential serial day numbers so that they can be used in calculations. By default, January 1, 1900, is serial number 1, and January 1, 2008, is serial number 39448 – because it is 39,447 days after January 1, 1900. The date returned by the calendar widget is always in the form of an Excel serial number.

Options for the Calendar widget


Required field requires input from the user. This option is mainly used for electronic forms, where a form must contain a minimum of information to be meaningful. For Calendar fields, a Required date cannot be empty – a designated date must appear in the widget cell. If the widget cell is empty, no date has been selected, and the form cannot be submitted.

Default date

If you don’t provide a default date, the calendar will position itself on the user’s current date but not select it. If you have selected the Required option, it is not fulfilled until the user explicitly clicks on a date to select it.

If you do provide a default date for a Calendar widget, your proposed default will appear in the field and the calendar will position itself on the default date, and it will be selected. To select a date other than the default, the user must select a different date in the calendar. If you have selected the Required option, it is always fulfilled when there is a default date, unless the user empties the date field or types an invalid date into it.

The default date assignment order

The default date can come from one of five sources. The assignment occurs in the order below, using the first valid date that is eligible. We call this the default date assignment order.

  1. The most recent value saved by a Real-time Sync session with the same key.
    Real-time Sync is a feature that allows multiple users to edit the same form or calculator simultaneously. With Real-time Sync, the contents of a form become persistent. You may return to a form years later and it will still contain the values from the most recent editing session.
  2. A date set by the query string for the link that invoked the form.
    You can assign a value to a date field from the link. You can either use an Excel serial number, e.g. /form.htm?built_date=20376 or your regional date format, e.g. /form.htm?built_date=10/14/1955. Read more about filling form fields from the link.
  3. A calculated default date from a formula cell.

    Screenshot of the default date setting for the Calendar widget

    If you select to assign a Calculated default date from another cell, you must select a formula cell in the spreadsheet from which the calculated default date is taken. When the Select another cell window appears, just select the formula cell (or type its cell reference into the window) and press OK.

    Screenshot of the Select another cell window

    In the formula cell, D10 in the example above, you can calculate the default date using any suitable formula, e.g. =TODAY()+7. The formula cell must contain a valid date in the form of an Excel serial number. For clarity, you may want to assign a date format to the formula cell, so that you can see what date it is returning to the Calendar widget. If you wish to provide a dynamic date as pre-filled input to the date calculation formula, you can use a hidden cell in the spreadsheet, e.g. “/form.htm?ship_on_default=20376”, and then your date calculation formula can pick this up and use it when selecting the default date, e.g. “=IF(OR(ship_on_default = “”, ship_on_default > 0), ship_on_default, TODAY()+30)”.

  4. The most recently used date from browser storage.
    If Browser Storage is enabled for a form, all form contents are saved in the browser. When the same form is opened again, it is prefilled with the data from the previous form submission in order to save time. Read more about Browser Storage.
  5. A fixed default date typed into the widget cell.
    You can provide a fixed default date simply by entering it into the widget cell in the source spreadsheet.

Regardless of how the default date is set according to the assignment priority above, the calendar will position itself on the default date, and it will be selected. With a valid default date in the cell, Required is always fulfilled.

Calendar style

There are two calendar styles:

  • The Button calendar is represented by a plain text field with a button in the form. The Full calendar appears when you press the button. The calendar disappears again when the user selects a date in the calendar.
  • The Pop-up calendar appears as a plain text field in the form. The Full calendar appears when you place the cursor in this field. The calendar disappears again when the user selects a date in the calendar.

Widget name

Name your widgets if you want to pass data into them from the link to the form (see above). For electronic forms, it makes it much easier to process the form if all input fields have names. You can name your fields in the widgets or give them cell names in Excel. Widget names can start with numbers or an underscore, which may be required when integrating with products like Salesforce.

Remove the calendar widget

Click on the Remove button to remove the calendar widget from the widget cell.

Hiding a calculated default date

As you can see in The default date assignment order above, you can use a separate formula cell to calculate a default date for the Calendar widget. You can use the same technique to put a fixed timestamp into each form, e.g. using the function =NOW().

In both cases, the cell contains a formula and will be locked for user input. It is not hidden by default, however. To hide a calculated date, insert a Utility widget into the formula cell and select Make hidden field. Even if you hide the default date in the web page, it will be included with the other form fields when the form is submitted.