What is an example of a matching and non-matching string?

A valid matching string is ""status": 200, "isClient": true, "name": "DevTransform"". A non-matching string is "{ empty: object }".

Is this regex safe from ReDoS (Catastrophic Backtracking)?

Yes, this pattern is optimized for linear execution time and safe for browser-side validation without locking up the UI thread.

HomeRegex LibraryJSON Key-Value Pair Extractor Regex

100% Client-Side • 0 B Data Leaves Browser

formatting

JSON Key-Value Pair Extractor Regex

Q: How do I test this regex in JavaScript and TypeScript?

Use regex.test(): const regex = /"([^"]+)"\s*:\s*("[^"]*"|\d+(?:\.\d+)?|true|false|null)/g; const isValid = regex.test(inputString);

Extracts property keys and primitive values (strings, numbers, booleans, null) from JSON data strings.

Regular Expression Pattern:

/"([^"]+)"\s*:\s*("[^"]*"|\d+(?:\.\d+)?|true|false|null)/g

Valid Match Example:

"status": 200, "isClient": true, "name": "DevTransform"

Invalid / Non-Match Example:

{ empty: object }

Regex Syntax Breakdown & Explanation

•"([^"]+)" : Captures JSON attribute key name
•\s*:\s* : Colon property delimiter with surrounding whitespace
•Second group captures string values, numbers, or boolean literals

Implementation in Popular Languages

JavaScript / TypeScript

const regex = /"([^"]+)"\s*:\s*("[^"]*"|\d+(?:\.\d+)?|true|false|null)/g;
const isValid = regex.test(""status": 200, "isClient": true, "name": "DevTransform"");
console.log(isValid); // true

Python (re)

import re

pattern = r""([^"]+)"\s*:\s*("[^"]*"|\d+(?:\.\d+)?|true|false|null)"
match = re.match(pattern, ""status": 200, "isClient": true, "name": "DevTransform"")
print(bool(match)) # True

Go (regexp)

package main
import (
  "fmt"
  "regexp"
)

func main() {
  re := regexp.MustCompile(`"([^"]+)"\s*:\s*("[^"]*"|\d+(?:\.\d+)?|true|false|null)`)
  fmt.Println(re.MatchString(""status": 200, "isClient": true, "name": "DevTransform""))
}

Frequently Asked Questions

Everything you need to know regarding specifications, syntax, and security best practices.

The regular expression pattern is /"([^"]+)"\s*:\s*("[^"]*"|\d+(?:\.\d+)?|true|false|null)/g. Extracts property keys and primitive values (strings, numbers, booleans, null) from JSON data strings.