What is a Phone Number Regex?

Phone numbers can appear in many formats, especially when supporting multiple countries. A regex (regular expression) helps match these patterns to ensure users enter valid contact numbers.

In Java, regex patterns for phone numbers commonly validate:

• Optional country codes (e.g., +91, +1)

• Numeric-only formats (e.g., 9876543210)

• Readable formats with dashes, spaces, or brackets (e.g., (123) 456-7890)

Building More Flexible Phone Number Regex Patterns

Creating regex patterns for phone number validation is often easiest when you start simple and layer in complexity as needed. Here’s how you can approach this process step by step:

1. Start with the basics:
Begin by matching plain, 10-digit numbers. This pattern is straightforward—simply look for exactly ten digits with no extra characters allowed.

2. Add formatting flexibility:
Once that’s working, expand your regex to accommodate common formatting variations. At this stage, you can allow optional spaces, hyphens, or dots between sections of the number. This makes your regex more forgiving and matches user input that includes formatting for readability.

3. Introduce parentheses:
To capture numbers commonly written with parentheses around the area code (like (123) 456-7890), adjust your regex to optionally recognize parentheses at the start. Make sure the rest of your pattern still allows for separators like spaces, hyphens, or dots.

4. Account for international prefixes:
Finally, improve global compatibility by allowing an optional international dialing prefix at the beginning. Usually, this means adding an optional plus sign (+) followed by up to three digits for the country code. You can also decide whether to accept a space after the country code, depending on typical international input formats.

By gradually introducing these enhancements, your regex evolves from a strict local validator into a robust pattern that gracefully accepts a wide range of real-world phone number formats. This layer-by-layer strategy is particularly helpful as user expectations and input styles can vary significantly based on geography and context.

Core Features

• Validates local and international phone numbers

• Supports formats with country codes, dashes, spaces, or brackets

• Helps improve data accuracy and prevent invalid submissions

• Java regex pattern preview and test output

• Real-time feedback for validation

  
  

Common Regex Patterns

1. Simple 10-digit number:

   
   Matches: 9876543210

   ^\d{10}$

   
   
   

2. International number with optional country code:
   
   

   Matches: +919876543210, 19876543210

   ^\+?[1-9]{1}[0-9]{7,14}$

   
   

3. Formatted US-style number:

   
   

   Matches: (123) 456-7890, 123-456-7890, 1234567890

   ^\(?\d{3}\)?[- ]?\d{3}[- ]?\d{4}$

Allowing Whitespaces, Dots, or Hyphens

Many modern phone numbers include spaces, dots, or hyphens for better readability. To accommodate these formats, you can use a regex pattern that allows optional whitespace, a dot (), or a hyphen () between number groups:

Pattern:

^\d{3}[-.\s]?\d{3}[-.\s]?\d{4}$

Matches:

• 2055550125

• 202 555 0125

• 202.555.0125

• 202-555-0125

Here, the portion of the regex enables separation of digits with an optional space, dot, or hyphen, making it flexible for various common phone number formats.

Use these patterns as a starting point and adapt as needed for your application's locale or formatting requirements.

Checking Multiple Phone Number Formats in Java

Sometimes, a single regex pattern isn’t flexible enough to capture all the different phone number styles you want to support. International numbers, regional connectors, and various formatting quirks mean you might need to validate against more than one regular expression.

In these scenarios, you can combine multiple regex patterns into a single pattern using the pipe symbol (``). The pipe acts as a logical “or,” allowing your validation to match if the input fits any of the listed patterns. This approach simplifies checks where formats might include:

• Numbers with or without parentheses, spaces, or dashes ((123) 456-7890, 123-456-7890)

• International styles (+111 123 456 789)

• Grouped digits with varying separators (+111 636 85 67 89)

Example usage:
Let’s say you have three patterns you want to support. You can join them like so:

String regex = "^(\\+\\d{1,3}( )?)?((\\(\\d{3}\\))\\d{3})[- .]?\\d{3}[- .]?\\d{4}$"
             + "^(\\+\\d{1,3}( )?)?(\\d{3}[ ]?){2}\\d{3}$"
             + "^(\\+\\d{1,3}( )?)?(\\d{3}[ ]?)(\\d{2}[ ]?){2}\\d{2}$";
Pattern pattern = Pattern.compile(regex);
Matcher matcher = pattern.matcher(phoneNumber);
boolean isValid = matcher.matches();

With this technique, you can validate a wide range of phone numbers by simply expanding or tweaking your patterns—making your Java validation resilient to nearly any format you encounter.

Combining Multiple Regex Patterns for Complete Phone Number Validation

When phone numbers come in a variety of formats, a single regex may not cover all cases. Instead, you can combine several regular expressions using the pipe symbol (``) to match different valid patterns. This approach is especially useful if your app needs to accept local formats, international numbers, and various separator styles (spaces, dashes, brackets, etc.).

Why combine patterns?
Because not every valid phone number shares the same structure. For instance, some might include country codes (+1 234 567 8901), while others stick with local 10-digit formats or use unique groupings and separators.

How to combine regexes in Java:
Simply list your regex patterns and join them using the pipe (``) to allow for matches against any of the specified styles. Here’s a quick example to illustrate this technique:

// Combine different patterns with the pipe operator
String patterns = "^(\\+\\d{1,3}( )?)?((\\(\\d{3}\\))\\d{3})[- .]?\\d{3}[- .]?\\d{4}$"
                + "^(\\+\\d{1,3}( )?)?(\\d{3}[ ]?){2}\\d{3}$"
                + "^(\\+\\d{1,3}( )?)?(\\d{3}[ ]?)(\\d{2}[ ]?){2}\\d{2}$";

Pattern pattern = Pattern.compile(patterns);

String[] validPhoneNumbers = {
    "2055550125",
    "202 555 0125",
    "(202) 555-0125",
    "+111 (202) 555-0125",
    "636 856 789",
    "+111 636 856 789",
    "636 85 67 89",
    "+111 636 85 67 89"
};

for (String phoneNumber : validPhoneNumbers) {
    Matcher matcher = pattern.matcher(phoneNumber);
    System.out.println(phoneNumber + ": " + matcher.matches());
}

Pro tip:
By chaining multiple expressions in this way, you can efficiently support a wide range of user inputs—without writing separate validation logic for each case.

How It Works

1. Enter your phone number in the input field.

2. Choose the regex pattern you want to test against.

3. The tool checks if your input matches and displays the result.

4. Use the output to validate real-time form entries or clean up datasets.

   
   

Example Code (Java)

import java.util.regex.Pattern;
import java.util.regex.Matcher;

public class PhoneNumberValidator {
    public static void main(String[] args) {
        String phoneNumber = "+1-234-567-8901";
        String regex = "^\\+?[1-9]{1}[0-9]{7,14}$";

        Pattern pattern = Pattern.compile(regex);
        Matcher matcher = pattern.matcher(phoneNumber);

        if (matcher.matches()) {
            System.out.println("Phone number is valid.");
        } else {
            System.out.println("Phone number is invalid.");
        }
    }
}

Validating Multiple Phone Number Formats

Phone numbers come in a variety of formats, making it tricky to cover every case with a single regular expression. If one pattern doesn’t catch everything you need, don’t worry—you can combine multiple regex patterns to cover more ground.

An effective approach is to define separate regex patterns for each desired format (for example, one for US numbers, another for international numbers), then join them using the pipe symbol (``). This tells the regex engine to check for a match against any of the specified patterns in a single pass.

For example, you might combine:

US format: (123) 456-7890 or 123-456-7890

String usPattern = ^\(?\d{3}\)?[- ]?\d{3}[- ]?\d{4}$

International: +919876543210 or 19876543210

String intlPattern = ^\+?[1-9]{1}[0-9]{7,14}$

Combine patterns with

String combinedPattern = usPattern + "" + intlPattern; Pattern pattern = Pattern.compile(combinedPattern);

This way, your validation logic becomes more flexible, ensuring you can support users from different regions without forcing everyone into one rigid format.

Feel free to tailor your patterns to your actual user base—just remember, when in doubt, test a variety of real-world numbers to make sure your regex is as inclusive (and accurate) as possible.

Pro Tips

• Use ^ and $ to anchor the pattern to the start and end of the string.

• Avoid overly strict regex for global apps—formats differ across countries.

• Use different regex patterns for validation and formatting (e.g., display vs input).

• Combine with form validation libraries for enhanced UX.

• For data imports, combine this tool with CSV to JSON Converter to clean phone numbers in bulk.

• For backend APIs, use this alongside the Java UUID Validator to validate user sessions.

Combine with These Tools

• Email Regex Java Validator — Validate user emails in the same system.

• UUID Regex Java Validator — Confirm identity tokens during authentication.

• Date Regex Java Validator — Ensure date formats in form fields are valid.

• Base64 Encoder — Encode sensitive information like phone numbers if needed.