---
title: "List of all FastField functions and variables"
slug: "list-of-all-fastfield-functions-and-variables"
updated: 2026-09-28T06:23:24Z
published: 2026-09-28T06:23:24Z
canonical: "help.quickbase.com/list-of-all-fastfield-functions-and-variables"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://help.quickbase.com/llms.txt
> Use this file to discover all available pages before exploring further.

# List of all FastField functions and variables

## Overview

FastField provides a range of functions that can be used in both [calculations](/fastfield/docs/the-calculation-field) and [field rules](/fastfield/docs/field-rules-and-skip-logic), allowing you to create dynamic forms with automated capabilities.

## List of functions

**float(value, emptyVal)** — safely converts a value to a floating point number

**string(value)** — converts value to a character string

**integer(value, emptyVal)** — safely converts a value to an integer

**bool(value)** — safely converts a value to a boolean (true/false)

**listContainsValues($list_field_key$, ['value 1', 'value 2'])** — checks if selected values from a List field contains a set of values

**listContainsValue($list_field_key$, ['value'])** — checks if selected values from a List field contains a single value

**concatenateSubformField($subform$, 'fieldKey', 'delimiter', includeEmptyValues)**

- **$subform$** - the field key on the main form of the subform field
- **'**[**fieldkey**](/fastfield/docs/what-are-field-keys-and-how-do-you-use-them)**' -** the field key in the subform that you want to pull into the main form
- **'delimiter'** - one or more characters that separate text strings; this can be any character (e.g., '|', '-', '/')
- **includeEmptyValues** - enter **true** or **false** here; this will either include or exclude empty values from the subform

**sumSection($section$, 'fieldkey')** — adds values across repeated sections (*learn more about [summing values across repeated sections](/fastfield/docs/how-do-i-sum-add-values-across-repeated-sections-advanced)*)

**sumSubform($subform$, 'fieldkey')** — sums values across multiple instances of a subform (*learn more about [summing values across subform instances](/fastfield/docs/how-do-i-sum-values-across-multiple-instances-of-a-subform)*)

**formatDate($dateField$, "format")** — outputs the date in a specified format

- **$dateField$** — the field key of the date field you want to reference
- **"format"** — enter the format you want to display the date using M, D, Y, such as "M/D/Y" or "Y-M-D"

**hoursBetween($startTime$, $endTime$)** — calculates the hours between two time fields

**daysBetween(startDay, endDay)** — calculates the number of days between two date fields

**countSubformInstances($subform$)** — used on the main form to return the number of subform instances for a given subform field

**countRepeatingSectionInstances($sectionKey$)** — calculate the number of instance for a repeating section

## Variables

| Variable | Email Subject/Body |
| --- | --- |
| [Sequence Number](/fastfield/docs/sequence-number) | [sequenceNumber] |
| Submission ID | [submissionId] |
| Account ID | [accountId] |
| Form Name | [formName] |
| Form ID | [formId] |
| Form Version | [formVersion] |
| Username | [userName] |
| User ID | [userId] |
| Last Updated Time | [updatedAt] |

**$subFormInstanceItemNumber$.** Use this in a calculation field to see which instance of the [subform](/fastfield/docs/adding-a-table-to-a-form-using-subforms) you are in. For the first instance of the subform it will display a *1*, for the second a *2*, and so on. You can use this as a counter within your subform or to create an incremental number within your subform.

**$CURRENT_USER_VAR$.** Used to pull in the username (email address) of the user logged into the [app](/fastfield/docs/using-the-fastfield-app) to complete the form.

**$mainform.fieldKey$.** Used in a subform to pull the value from a field in the main form.

**$fieldkey.timestamp$.** Used to pull the timestamp captured for a specific field.

**$formMetadata.submissionId$.** Used to pull in the submission ID.

**$formMetadata.startFormTimeStamp$.** Used to pull in the date and time a form was started.