---
title: "Regular Expression Steps"
slug: "regular-expression-steps"
description: "Use Regular Expressions to validate text input in Decisions, including formats such as phone numbers and email addresses."
tags: ["regular expression"]
updated: 2026-06-26T13:55:10Z
published: 2026-06-26T13:55:10Z
canonical: "documentation.decisions.com/regular-expression-steps"
---

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

# Regular Expression Steps

## Overview

**Regular** **Expressions** **(Regex)** are patterns written in a formal language that can be interpreted by a regular expression processor to serve the function of text validation. Listed below are steps that use specific Regular Expressions to validate text input such as a phone number or email.

---

## Regular Expression Steps

The Regular Expression Steps are located in the **Toolbox panel** under **DATA > TEXT**.

![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/image-1778526936302.png)

### Regex Does Not Match

The **Regex Does Not Match** step returns a true or false result if the validated String does not match the Input/Regex Patter.

| Input Parameter | Description |
| --- | --- |
| Input | String value |
| Pattern | Regular expression pattern |

![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/image-1778527049760.png)

### Regex Get Matches

The **Regex Get Matches** step returns a count of matched results against a Regex text validation.

| Input Parameter | Description |
| --- | --- |
| Input | String value |
| Regex | Regular expression pattern |

![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/image-1778527131874.png)

### Regex Get Matches Advanced

The Regex Get Matches Advanced step returns a list of matched validations utilizing a Regex pattern, a text input, and additional Regex options if desired.

| Input Parameter | Description |
| --- | --- |
| Input | String value |
| Options | Additional options to use with the Regular Expression |
| Pattern | Regular Expression |

![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/image-1778527301037.png)

![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/image-1778527247612.png)

### Regex Match

The **Regex Match** step returns a true or false as the result of Regex validation.

| Input Parameter | Description |
| --- | --- |
| Input | String value |
| Pattern | Regular Expression pattern |

![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/image-1778527437862.png)

### Regex Replace

The **Regex Replace** step looks up text input by the Regular Expression pattern and replaces text that matches the pattern.

| Input Parameter | Description |
| --- | --- |
| Input | String value |
| Options | Additional options for the Regular Expression |
| Pattern | Regular Expression pattern |
| Replacement | String value to replace input |

![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/image-1778527714686.png)

### Regular Expression

The Regular Expression step is used to identify patterns within Strings

| Input Parameter | Description |
| --- | --- |
| Input | String input value |

![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/image-1778527839540.png)

---

## Common Use Case Patterns

The following **Regex** **Patterns** can be used in conjunction with the **Regex** **Match** step to perform some common text validation. For further information on **Regular** **Expressions** and how to configure them see: [Microsoft: Regular Expression Language Quick Reference.](https://docs.microsoft.com/en-us/dotnet/standard/base-types/regular-expression-language-quick-reference)

| Type of Validation | Regex Pattern |
| --- | --- |
| Email | ^\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*$ |
| Routing Number | ^((0[0-9])\|(1[0-2])\|(2[1-9])\|(3[0-2])\|(6[1-9])\|(7[0-2])\|80)([0-9]{7})$ |
| Phone Number | \(?\d{3}\)?-? *\d{3}-? *-?\d{4} |
| String (Only Numbers) | ^[0-9]+$ |
| Zip Code | ^\d{5}(?:[-\s]\d{4})?$ |

### Regex Match Example

The following example demonstrates the **Regex Match** step to see if a user inputted String is a zip code.

1. [Create a Flow](/version-10/docs/creating-your-first-flow-2)
2. [Create a Form](/version-10/docs/create-a-form) that takes in a user input using a Textbox control.
3. Define a Data Name for the Textbox control![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/image-1778528062104.png)
4. In the Toolbox, expand **Data > Text** and place the **Regex Match** step onto the workspace.
5. For the steps inputs, select the Form's output for the **Input** field and set **Pattern** as a constant.  
Since a regular expression for zip code is being used, the following pattern was used: ^\d{5}(?:-\d{4})?$**![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/image-1778528367680.png)**
6. Add a **Show Popup** step to the outcome paths of the **Regex Match** step.
7. The inputs can be defined as a **Constant** for the **Show Popup** step![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/image-1778528418504.png)
8. Debug the Flow. The pattern and the inputted String will determine the outcome path of the Flow.![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/image-1778528527801.png)