> For the complete documentation index, see [llms.txt](https://docs.senpiper.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.senpiper.com/form-builder/creating-forms/additional-form-settings/conditions/calculate-field-values.md).

# Calculate field values

This feature is used to apply values from specific fields to calculate the value of other fields.

![](/files/q3NXTjERqG2kBhBgJD1Q)

To calculate a field value,

1\.    Under **Calculate field values**, to enter a condition for calculating field values, click **Set condition**.

Let's say we there are 3 fields in a form: **Number of days**, **Expense per day** and **Total expense**. The **Total expense** can be calculated by using the formula: **Total expense = Number of days \* Expense per day**. Let's add in a condition that the **Total expenses** field will only be auto-calculated if the **Number of days** is greater than 1.

2\.    To configure a condition for the calculation of a value for the field, under **Calculate field values**, click **Set condition**.

![](/files/306TmsKFk32RyrMybBub)

The **Set condition** screen is displayed.

![](/files/vSjmqdDleP9cuB1NVO5K)

2\.    To add a condition, click **Add rule**.

The option to add a condition is displayed.

![](/files/cKZRpiUhhgVwsZG7c7bN)

3\.    To enter the condition, enter the required field name, operator and the field value and then click **Apply**. 

The condition is added in the **Calculate field values** tab.

3\.    In the text area, enter the required formula using the keypad on the right.

![](/files/GCjJgTkKBS667zoKg4N5)

{% hint style="info" %}
To use the standard math functions namely algebraic, logarithmic  and trigonometric functions, click Add func.
{% endhint %}

> Add func. has 2 categories: Custom functions and Math functions. 
>
> Math functions are algebraic, logarithmic  and trigonometric functions. 
>
> Custom functions includes some commonly used custom made javascript expressions like getDate(), getMonth(), Sum(), average() and more. 

 The **Paste formula** is auto-filled based on the formula entered in the text area.

4\.    In **Select field for final output**, select the field in which the calculated value is to be displayed. 

5\.    To save the settings, at the bottom right of the screen, click **Save**.

Based on the formula and settings configured above, the **Total expense** field will be auto-filled whenever the **Number of days** field has a value greater than 1.

![](/files/SuKsco0ShGxgnZMN6Cmd)