BytePane

Integer Regex Pattern

Matches whole numbers including negative values. Simple pattern for validating integer input in forms or data processing.

#
Numbers
Beginner
Difficulty
Universal
Language
none
Flags
// Regular Expression
/^-?\d+$/

Live Regex Tester

Pattern Breakdown

^-?\d+$
Character class [ ]
Group ( )
Quantifier { }
Anchor ^ $
Repetition * + ?
Escape \
Alternation |
Any char .

Code Examples

JavaScript

const regex = /^-?\d+$/;
const test = "-42";
console.log(regex.test(test)); // true

// Extract matches
const matches = test.match(regex);
console.log(matches);

Python

import re

pattern = r'^-?\d+$'
test = "-42"
match = re.search(pattern, test)
print(match)  # Found!

Go

package main

import (
    "fmt"
    "regexp"
)

func main() {
    re := regexp.MustCompile(`^-?\d+$`)
    fmt.Println(re.MatchString("-42")) // true
}

Common Use Cases

Input validationnumber parsingdata filtering

Match Examples

InputResult
-42Match
3.14No Match

About the Integer Regex

Matches whole numbers including negative values. Simple pattern for validating integer input in forms or data processing.

Regular expressions (regex) are powerful pattern matching tools used across virtually all programming languages. The integer pattern is classified as beginner difficulty in the numbers category. It works in all major programming languages.

When using this regex, always consider edge cases and test thoroughly with real-world data. Use the interactive tester above to validate the pattern against your specific inputs before deploying to production.

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Frequently Asked Questions

What is the Integer regex pattern?

Matches whole numbers including negative values. Simple pattern for validating integer input in forms or data processing.

How do I use the Integer regex?

Use the pattern /^-?\d+$/ in your code. In JavaScript: new RegExp('^-?\d+$', ''). Test it above with your own input.

What does this Integer regex match?

This pattern matches: "-42". It does NOT match: "3.14". Input validation, number parsing, data filtering.

Is the Integer regex beginner-friendly?

This pattern is rated Beginner. It uses basic regex syntax and is easy to understand.

What languages support the Integer regex?

This pattern works in all major programming languages including JavaScript, Python, Java, C#, Go, Ruby, PHP, and more. Syntax may vary slightly between regex engines.

Can I modify the Integer regex for my use case?

Yes! Use the interactive tester above to modify the pattern and test with your own data. Common modifications include making it case-insensitive (add 'i' flag), matching globally (add 'g' flag), or adjusting character classes.

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