# Formula field

#### Who can use this feature?

👤  Available on all plans.

Formulas let you transform and combine existing fields into a new Formula field. For example, you can:

• Concatenate `First name` and `Last name` fields into a `Full name` Formula field.
• Multiply `Price` and `Units` field to get the result in the `Revenue` Formula field.

The field will show only in your Stacker app, and won't show up in your Airtable base or Google Sheets.

## Create a formula field

1. Go to  Manage Fields and data > [Table name] > Fields
2. Click Add field > Formula
4. Click Save

Press space in the formula field box to see a list of all available fields and functions.

## Fields in formulas

To use a field in a formula, the field needs to be in the table where you're creating the formula field. It also needs to be one of the following data types:

• Text
• Long Text
• Number
• Checkbox
• URL
• Single Select Dropdown
• Percentage
• Currency
• Rich Text
• Date
• Date and Time
• Multiple Select Dropdown

To use a field in a formula, you will need to wrap it in curly brackets. For example, {Price}. If you type in the opening curly bracket, we will suggest all available fields. ## List of formulas

Functions work with any valid field data types, while operators work only on number fields. If you use an operator for a non-number field, we will try to convert it into a number. If we can't, you'll see an error message.

Operator Function

#### SUM

Returns the sum of two or more numbers.

Example:

`SUM({Sold},{Not sold})`

or

`{Sold} + {Not sold}`

#### SUBTRACT

Returns the difference of two numbers.

Example:

`{Total stock} - {Sold stock}`

#### MULTIPLY

Returns the product of two numbers.

Example:

`{Sold} * {Price}`

#### DIVIDE

Returns one number divided by another.

Example:

`{Total sold} / {Price}`

#### AVERAGE

Returns the average of the values in two or more fields.

Example:

`AVERAGE({Sold},{Not sold})`

#### NOT EQUAL TO

Check if one value is not equal to another.

Example:

`1!=2 =>True` (represented as a checked checkbox)

#### EQUAL TO

Compare if one value is equal to another value.

Example:

`1=1 =>True` (represented as an empty checkbox)

#### GREATER THAN

Compare if one value is greater than another value.

Example:

`1>5 =>False` (represented as an empty checkbox)

#### GREATER THAN OR EQUAL TO

Compare if one value is greater than or equal to another value.

Example:

`2<=2 =>True` (represented as a checked checkbox)

#### LESS THAN

Compare if one value is less than another value.

Example:

`5>1 =>False` (represented as an empty checkbox)

#### LESS THAN OR EQUAL TO

Compare if one value is less than another value.

Example:

`2<=2 =>True` (represented as a checked checkbox)

## Error messages

If a formula is invalid, you will see an error message that might help you understand what went wrong.

 Error Meaning `Missing formula function` or `Unexpected formula function` Means that you were very creative, but we don't have the formula function yet. `Function only works with field_type but field is a another_field_type` Shows when using a field with an incompatible field type. ```In an IF function, field_name and field_name_2 must be of similar types``` Shows in an IF function when the Action A and Action B are different types. `Missing keys in formula 'IF' function: else` Means that there is a missing else (Action B) in the IF function.