Regex for Indian Phone Number Validation — +91, 91, and 10-Digit Formats

Indian users enter their mobile number in a handful of common ways — sometimes with the +91 country code, sometimes with a plain 91 prefix, and often as just the bare 10-digit number. A validation regex that only supports one of these formats will reject a large share of legitimate users. This guide gives you a pattern that handles all three, plus JavaScript and Python examples.

Understanding the number format

An Indian mobile number has two parts that matter for validation:

• An optional country code — either +91 or bare 91.
• A 10-digit subscriber number that must start with 6, 7, 8, or 9 — the only digits DoT allocates for mobile number series.

Valid examples include 9876543210, 919876543210, and +919876543210.

The phone number regex pattern

^(?:\+91|91)?[6-9][0-9]{9}$

The non-capturing group (?:\+91|91)? makes the country code optional, and [6-9][0-9]{9} enforces the correct starting digit and total length of 10 digits.

JavaScript example

function isValidIndianMobile(number) {
  const cleaned = number.replace(/[\s()-]/g, "");
  const phoneRegex = /^(?:\+91|91)?[6-9][0-9]{9}$/;
  return phoneRegex.test(cleaned);
}

console.log(isValidIndianMobile("+91 98765-43210")); // true
console.log(isValidIndianMobile("9876543210"));       // true
console.log(isValidIndianMobile("5876543210"));       // false - starts with 5
console.log(isValidIndianMobile("+91987654321"));     // false - only 9 digits after code

Python example

import re

PHONE_REGEX = re.compile(r"^(?:\+91|91)?[6-9][0-9]{9}$")

def is_valid_indian_mobile(number: str) -> bool:
    cleaned = re.sub(r"[\s()-]", "", number)
    return bool(PHONE_REGEX.match(cleaned))

print(is_valid_indian_mobile("+91-98765-43210"))  # True
print(is_valid_indian_mobile("098765 43210"))      # False - leading 0 not allowed

Extracting just the 10-digit number

For storage, it's usually best to normalize every valid input down to the bare 10-digit form rather than keeping the country code inconsistently:

function normalizeIndianMobile(number) {
  const cleaned = number.replace(/[\s()-]/g, "");
  const match = cleaned.match(/^(?:\+91|91)?([6-9][0-9]{9})$/);
  return match ? match[1] : null;
}

console.log(normalizeIndianMobile("+91 98765 43210")); // "9876543210"

Common mistakes to avoid

• Hardcoding only the +91 prefix and rejecting bare 91 or plain 10-digit input — all three are valid user-facing formats.
• Forgetting to restrict the first digit to 6-9, which lets invalid landline-range numbers slip through as "valid" mobile numbers.
• Not stripping spaces, hyphens, or parentheses before validating, which causes naturally formatted input like 98765 43210 to fail unnecessarily.

Frequently Asked Questions