What is the regex for data url?

The regex pattern for data url is `^data:([a-zA-Z]+\/[a-zA-Z0-9.+-]+)?(;base64)?,`. This pattern validates matches data: url scheme with optional mime type and base64 encoding.

How do I use this regex in JavaScript?

In JavaScript, create the regex with `const regex = /^data:([a-zA-Z]+\\/[a-zA-Z0-9.+-]+)?(;base64)?,/;` 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'^data:([a-zA-Z]+\/[a-zA-Z0-9.+-]+)?(;base64)?,', value)`. The raw string prefix (`r`) prevents Python from interpreting backslashes as escape characters.

Is this regex case-sensitive?

This pattern explicitly handles both uppercase and lowercase via the character classes. No additional flags needed.

Regex for Data URL

Regex Pattern

^data:([a-zA-Z]+\/[a-zA-Z0-9.+-]+)?(;base64)?,

Matches data: URL scheme with optional MIME type and base64 encoding

Quick Answer

The regex pattern for data url is `^data:([a-zA-Z]+\/[a-zA-Z0-9.+-]+)?(;base64)?,`. Matches data: URL scheme with optional MIME type and base64 encoding. This works in JavaScript, Python, Ruby, PHP, Java, and most regex engines that support PCRE syntax.

Test Examples

Input	Result
data:text/plain,Hello	✓ Matches
data:image/png;base64,iVBOR	✓ Matches
data:,plaintext	✓ Matches
http://example.com	✗ No match
data:	✗ No match
not-a-data-url	✗ No match

Code Examples

javascript

const regex = /^data:([a-zA-Z]+\\/[a-zA-Z0-9.+-]+)?(;base64)?,/;
const isValid = regex.test(value);

python

import re
pattern = r'^data:([a-zA-Z]+\/[a-zA-Z0-9.+-]+)?(;base64)?,'
if re.match(pattern, value):
    print("valid")

ruby

pattern = /^data:([a-zA-Z]+\/[a-zA-Z0-9.+-]+)?(;base64)?,/
if value =~ pattern
  puts "valid"
end

php

if (preg_match('/^data:([a-zA-Z]+\\/[a-zA-Z0-9.+-]+)?(;base64)?,/', $value)) {
    echo "valid";
}

java

String pattern = "^data:([a-zA-Z]+\\/[a-zA-Z0-9.+-]+)?(;base64)?,";
boolean isValid = value.matches(pattern);

Frequently Asked Questions

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