Phone Number Regex: Validate Phone Numbers

Use these phone number regex patterns to validate phone numbers in forms and apps. Below you will find practical patterns for digits-only, formatted, and international numbers, plus copy-ready examples for JavaScript, Python, and HTML.

Phone number regex

There is no single perfect regex for every phone number format. Start by deciding whether you need digits only, a flexible user-input format, or an international number with a leading +.

Digits-only regex:

^\d+$

Flexible phone number regex:

^\+?[\d\s\-()]+$

International-style regex:

^\+[1-9]\d{1,14}$

What the flexible regex matches:

• 1234567890
• +1 555 123 4567
• (555) 123-4567
• +44 20 7946 0958

What it does not match:

• abc1234567
• 555-EXT-99
• ++1 555 123 4567

Quick note: If you need production-grade international validation, regex alone is usually not enough. Use regex for format checks and a phone parsing library for full validation.

The basic international phone number validation

A simple regex to validate string against a valid international phone number format without delimiters and with an optional plus sign:

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

Example code in Javascript

// Validate phone number
const validatePhoneNumberRegex = /^\+?[1-9][0-9]{7,14}$/;
validatePhoneNumberRegex.test('+12223334444'); // Returns true

// Extract phone number from a string
const extractPhoneRegex = /\+?[1-9][0-9]{7,14}/g;
'You can reach me out at +12223334444 and +56667778888'.match(extractPhoneRegex); // returns ['+12223334444', '+56667778888']

The more complex phone number validation

This regular expression will match phone numbers entered with delimiters (spaces, dots, brackets, etc.)

/^\+?\d{1,4}?[-.\s]?\(?\d{1,3}?\)?[-.\s]?\d{1,4}[-.\s]?\d{1,4}[-.\s]?\d{1,9}$/

Example code in Javascript

var regex = /^\+?\d{1,4}?[-.\s]?\(?\d{1,3}?\)?[-.\s]?\d{1,4}[-.\s]?\d{1,4}[-.\s]?\d{1,9}$/;
regex.test('+1 (615) 243-5172'); // returns true

Common mistakes

1. Expecting one regex to cover every country and format

Phone numbers vary a lot by country, length, separators, and local conventions. A short regex can help with format validation, but it cannot fully understand all real phone number rules.

2. Using digits-only validation when users type formatted numbers

If your users enter values like:

• +1 555 123 4567
• (555) 123-4567
• 020 7946 0958

then a digits-only regex will reject valid user input.

3. Treating regex as real phone verification

Regex does not tell you whether:

• the country code is valid
• the number is assigned
• the number can receive SMS or calls

If you need that, use a parsing or verification service.

4. Mixing validation and normalization

These are different goals:

• validation checks whether the input format is acceptable
• normalization converts the input into a standard format such as E.164

Usually you need both.

Extra information about validating phone number

While validation of phone numbers using regex can give a possibility to check the format of the phone number, it does not guarantee that the number exists.

There might be also an option to leave a phone number field without any validation since some users might have:

• More complex phone numbers with extensions
• The different phone numbers for calling them on a different time of day