The Calculation field in Formester allows you to perform custom math operations inside your form. You can add numeric fields (like number inputs, price, or quantity) and then use formulas to calculate totals, scores, or other values. This is perfect for order forms, quizzes, and estimators.

Adding a Calculation Field

• Open your form in the Formester editor.
• Click Add Elements.
• Scroll to Others and select Calculation.
• A new calculation field will appear on your form.

Setting Up a Formula

• Click on the Calculation field to open the Properties panel.
• In the formula editor, type your expression.
• Use the @ sign to recall any numeric field from your form.

Example:

If your form has a field for Quantity and a field for Price, you can write:

@Quantity * @Price

This will automatically calculate the total.

Supported Operations

You can use:

• Addition (+) → @Field1 + @Field2
• Subtraction (-) → @Field1 - @Field2
• Multiplication (*) → @Field1 * @Field2
• Division (/) → @Field1 / @Field2
• Parentheses for order of operations → (@Field1 + @Field2) * @Field3

Using Default Values

• You can assign a default value to numeric fields.
• When recalled with @, the formula will automatically include them.

Example: A tax rate field with default value 0.18 can be included in your calculation.

Displaying the Result

• You can rename the Calculation field label to match your use case.
• Example: “Order Total”, “Final Score”, “Estimated Cost”.
• The result updates automatically as users change input values.

Use Cases

• Order Forms: Calculate product totals with quantity and price.
• Quizzes: Add scores automatically based on user answers.
• Cost Estimators: Estimate pricing for services based on user selections.
• Surveys: Sum up numeric ratings to give a total satisfaction score.

Publish and Test

• Click Publish once your formula is ready.
• Preview your form and test different inputs to confirm your calculations are correct.

Updated on: 15/09/2025