What is the regex for year (4-digit)?

The regex pattern for year (4-digit) is `^(?:19|20)\d{2}$`. This pattern validates four-digit year between 1900 and 2099.

How do I use this regex in JavaScript?

In JavaScript, create the regex with `const regex = /^(?:19|20)\d{2}$/;` and test with `regex.test(yourValue)`. It returns `true` if the value matches.

How do I use this regex in Python?

In Python, use `import re; re.match(r'^(?:19|20)\d{2}$', value)`. The raw string prefix (`r`) prevents Python from interpreting backslashes as escape characters.

Is this regex case-sensitive?

By default, yes. To make it case-insensitive, add the `i` flag in JavaScript (`/^(?:19|20)\d{2}$/i`) or use `re.IGNORECASE` in Python.

Regex for Year (4-digit)

Regex Pattern

^(?:19|20)\d{2}$

Four-digit year between 1900 and 2099

Quick Answer

The regex pattern for year (4-digit) is `^(?:19|20)\d{2}$`. Four-digit year between 1900 and 2099. This works in JavaScript, Python, Ruby, PHP, Java, and most regex engines that support PCRE syntax.

Test Examples

Input	Result
2026	✓ Matches
1999	✓ Matches
2000	✓ Matches
1900	✓ Matches
26	✗ No match
99	✗ No match
2100	✗ No match
1899	✗ No match

Code Examples

javascript

const regex = /^(?:19|20)\d{2}$/;
const isValid = regex.test(value);

python

import re
pattern = r'^(?:19|20)\d{2}$'
if re.match(pattern, value):
    print("valid")

ruby

pattern = /^(?:19|20)\d{2}$/
if value =~ pattern
  puts "valid"
end

php

if (preg_match('/^(?:19|20)\d{2}$/', $value)) {
    echo "valid";
}

java

String pattern = "^(?:19|20)\\d{2}$";
boolean isValid = value.matches(pattern);

Frequently Asked Questions

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