Compute Field Value & Formulas

The Compute field value rule action writes a calculated value into a target field when a rule fires. Alongside the simple operations (Sum, Subtract, Multiply, Divide, Concatenate, Date offset, Date difference) it now supports a Formula expression operation — a free-form, Excel-style formula evaluated when the rule runs.

The Compute field value action is not related to SharePoint’s built-in Calculated column type — it runs in the form, in the browser, when your rule triggers.

1. Referencing field values

Use either form to insert a field’s current value into your formula:

• [[fieldValue:InternalName]] — the explicit token
• [InternalName] — shorthand

Wrap field references in quotes when comparing them as text: "[[fieldValue:Severity]]"=="Critical".

2. Supported functions

IF, AND, OR, NOT,
CONCATENATE, UPPER, LOWER, PROPER, TRIM, LEFT, RIGHT, LEN,
ROUND, FLOOR, CEILING, ABS, MIN, MAX, VALUE, TEXT,
ISNUMBER, ISBLANK,
TODAY, NOW, DATEADD, DATEDIF

Operators: use == for equality and != for not-equal. <, >, <=, >= work for numbers and dates. Arguments are separated by commas (not semicolons).

3. Examples

// Conditional text based on a choice field value
IF("[[fieldValue:Severity]]"=="Critical", "Requires immediate attention — escalate now", "No escalation needed")

// Nested IF for multiple outcomes
IF("[[fieldValue:Severity]]"=="Critical", "P1 — act now",
   IF("[[fieldValue:Severity]]"=="High", "P2 — review today", "P3 — normal queue"))

// Line total with rounding to 2 decimals
ROUND("[[fieldValue:Quantity]]" * "[[fieldValue:UnitPrice]]", 2)

// Days remaining until a deadline
DATEDIF(TODAY(), "[[fieldValue:DueDate]]", "days")

// Build a display name, tidy casing and trim stray spaces
PROPER(TRIM(CONCATENATE("[[fieldValue:FirstName]]", " ", "[[fieldValue:LastName]]")))

// Flag an order as large only when a real number was entered
IF(AND(ISNUMBER("[[fieldValue:Amount]]"), "[[fieldValue:Amount]]" >= 10000), "Large order", "Standard")

4. Using the editor

Click the formula icon on the Compute field value action to open a dedicated editor with:

• Syntax highlighting
• Autocomplete — type [ to get field suggestions; function names autocomplete too
• An examples panel and a full function reference
• A live syntax validator that checks the formula as you type and reports problems in plain language:
  • Missing or extra closing parenthesis
  • Unknown function name (e.g. typing RND instead of ROUND)
  • Semicolons used instead of commas as argument separators
  • A single = used where == is required for equality

5. Setting it up

1. Create or edit a rule and add the Compute field value action.
2. Set the operation to Formula expression.
3. Choose the target field that receives the result.
4. Click the formula icon and write your expression.
5. Pick the rule’s trigger (e.g. on change of a field, or form pre-save) so the formula recalculates at the right time.

Tip: to keep a computed total always up to date, trigger the rule on change of each input field. To compute something only at save time (e.g. a reference code), trigger on form pre-save.