Defining calculation fields
Use calculation fields to perform calculations on the following types of data: text, number, date, time, or container.
The data in a calculation field is the result of a formula that you specify. The result can be one of these types of data: text, number, date, time, or container.
To define calculation fields:
1.
With the file open, choose File menu > Manage > Database.
2.
In the Manage Database dialog box, click the Fields tab.
3.
If your file contains more than one table, select the appropriate table from the Table list.
4.
For Field Name, type a name for the field.
See About naming fields.
5.
For Type, select Calculation.
6.
Click Create.
You see the Specify Calculation dialog box.
7.
If necessary, for Evaluate this calculation from the context of, choose a table from the list.
Setting the context for a calculation is only necessary when you're creating a calculation field in a source table that has two or more occurrences in the relationships graph. The choice you make may affect the calculation results, particularly if your calculation will include fields in related tables. See Choosing the evaluation context for a calculation field.
8.
Build a formula for your calculation using field references, operators, constant values, and functions.
In the calculation pane, click where you want the item to appear, then:
 
To add
Do this
A reference to a field
Do one of the following:
 •
Begin typing the field’s table, choose the table from the list, begin typing the field name, then choose the field name from the list that appears.
 •
In the fields pane, double-click the field name. To display field names from a different table, choose the table from the tables list.
An operator or an exponent
Do one of the following:
 •
Type an operator.
 •
Click an operator in the list to the right of the calculation pane.
See Comparison operators, Logical operators, Mathematical operators, and Text operators.
A constant value
Type the value.
A function
Do one of the following:
 •
Begin typing the function name, then choose the function name from the list that appears.
 •
In the functions pane, double-click the function.
In the calculation pane, replace the placeholder parameter with a value or expression.
9.
Specify calculation options for the field.
 
To
Do this
Set the field type of the result
Choose a data type for Calculation result is <value>.
Choose the correct type for the result you want. See About choosing a field type.
Make a calculated field repeating
For Number of repetitions, type the number of repetitions. See Defining repeating fields.
Prevent calculation if all referenced fields are empty
Select Do not evaluate if all referenced fields are empty.
When enabled, FileMaker Pro does not evaluate a calculation if all fields used by the calculation are empty.
10.
To select indexing and storage options for the field, click Storage Options, choose options in the Storage Options dialog box, then click OK.
See Defining field indexing options and Defining global fields (fields with global storage).
11.
Click OK to close the Specify Calculation dialog box.
12.
Continue to define fields or click OK.
Important  To avoid confusion when using dates in FileMaker Pro, always define calculation formulas to enter four-digit years. For information on how FileMaker Pro handles dates with two-digit years, see Conversion of dates with two-digit years.
To define calculation fields in Table View:
1.
With the database open in Browse mode, click Table View Table View button in the layout bar.
2.
Click + in the column heading to add a new field.
3.
Right-click the column heading for the new field, then choose Field > Field Type > Calculation from the shortcut menu.
4.
Build a formula for calculation and specify options for the field in the Specify Calculation dialog box.
Notes
 •
To show or hide the functions pane, click Show/hide functions pane button in the Specify Calculation dialog box.
 •
To filter the list of fields or functions in the fields pane or the functions pane, type the field name or function name in the search box.
 •
To change the way fields or functions are displayed in the fields pane or the functions pane, click .
 •
A calculation field calculates a result from values in other fields in the current record, from related records using a relationship, or from fields defined with global storage options. (In contrast, a summary field produces a result using values in more than one record in the database. See Defining summary fields.)
 •
Calculation fields are updated when a value in the calculation changes. Unstored calculation fields are also updated when the record is refreshed, the field is clicked or tabbed into or out of, or the field is refreshed (for example, by a script).
 •
Values, expressions, functions, and parameters can be uppercase or lowercase.
 •
To include literal quotation marks in a calculation text string, precede the quotation mark character with a backslash character (\). For, example, “Hello” included in a calculation evaluates to Hello, but “\”Hello\”” evaluates to “Hello”.
 •
FileMaker Pro calculates the formula when you close the Manage Database dialog box. There may be a delay if your database contains many records (for example, 10,000).
 •
Calculations that include a related field, summary field, global value, or a reference to another unstored calculation are unstored.
 •
Calculations defined with global storage options display values calculated using the last modified record.
 •
If any field on a layout containing unstored calculations is set to auto-resize, calculation results will be updated when the window is resized.
 •
You can reference container fields in calculations and display container data in calculation fields. See About container fields.
 •
References to related fields can become invalid if the related file is missing, or if you delete a field in the related file. FileMaker Pro alerts you that a field reference is invalid when you display or change the calculation formula. Changing the field type in a related file may cause unexpected behavior.
 •
If your FileMaker Pro file accesses data from an ODBC data source, you can use supplemental fields to define unstored calculations or summary instructions that act on data coming from the external sources. See Using supplemental fields.
 •
If you are using FileMaker Pro Advanced, you can copy field schemas from one file and paste them into the same file or some other file. See Copying and pasting field schemas (FileMaker Pro Advanced).
Calculation examples
 
Field name
Field type
Calculation
Today’s Date
Date
Get( CurrentDate )
Full Name
Text
FirstName & “ ” & LastName
Sales Tax
Number
SubTotal * .08
Related topics 
About formulas
Working with formulas and functions
About functions
Changing calculation formulas
Formatting and setting up field objects in Layout mode
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