Build custom regex patterns easily and test them in real-time with instant results.
Regex Builder is a smart online tool that helps you create and test regular expressions easily. Regular expressions, also known as regex, are a powerful way to search, match, and manipulate text. However, writing regex manually can be confusing and time-consuming. This tool solves that problem by providing a guided interface where you can build expressions step by step and test them instantly on any input text.
Regex is used in almost every programming language including JavaScript, Python, PHP, Java, C#, Ruby, Go, and more. It helps in validating data formats, finding patterns, extracting useful information, replacing text, and filtering content. For example, if you want to check if a string is a valid email, regex is the best solution. If you want to find all numbers inside a text, again regex is the fastest way.
Many people are afraid of regex because the syntax looks complicated. But with Regex Builder, you don’t need to remember everything. Just choose options, enter your text, and the tool will generate the correct regex automatically. Live testing makes it easy to understand how each part of the pattern works. This tool is helpful for beginners as well as professionals who want to save time during development.
Regex Builder is made for everyone who works with text and data:
Below are some useful patterns you can create using this tool:
| Purpose | Example Regex |
|---|---|
| Email validation | ^[a-z0-9._%+-]+@[a-z0-9.-]+\.[a-z]{2,}$ |
| Phone number | ^\+?[0-9]{10,13}$ |
| Postal code | ^[0-9]{5,6}$ |
| Username | ^[a-zA-Z0-9_]{4,16}$ |
| Hex color | ^#?([a-fA-F0-9]{6}|[a-fA-F0-9]{3})$ |
Let’s say you want to create a regex to validate a password. It should:
You can select these options in Regex Builder, and the tool will automatically generate:
^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[@$!%*?&]).{8,16}$
Regex is an important topic in computer science and programming interviews. Students who practice with Regex Builder can understand the logic, learn important syntax, and quickly test their knowledge. It also helps in assignments, projects, and coding competitions. The tool acts like a tutor that explains how each part of regex works.
Write any string or paragraph where you want to extract or validate data.
Select digits, characters, symbols, or custom options.
The tool will generate your regex and highlight matching results instantly.
You can directly use it in JavaScript, Python, PHP, or any language.
Regex works in almost every programming language. Here are some examples:
const pattern = /^[a-z0-9._%+-]+@[a-z0-9.-]+\.[a-z]{2,}$/;
console.log(pattern.test("example@mail.com"));
import re
pattern = r'^[a-z0-9._%+-]+@[a-z0-9.-]+\.[a-z]{2,}$'
print(bool(re.match(pattern, "example@mail.com")))
$pattern = '/^[a-z0-9._%+-]+@[a-z0-9.-]+\.[a-z]{2,}$/';
if (preg_match($pattern, "example@mail.com")) {
echo "Valid Email";
}
Regex is a powerful tool for working with text data. With Regex Builder, anyone can create accurate expressions without confusion. It improves speed, learning, and productivity. Whether you are a beginner or an experienced developer, this tool will become a daily part of your workflow. Try different patterns and test them directly in your browser.