A simple key-value string parser with zero dependencies. Designed for single-line key-value strings with support for numbers, quoted strings, and arrays. Perfect for configuration strings, URL parameters, and command-line arguments.

Thoroughly tested with 200+ unit tests to ensure reliability and edge case handling.

npm install key-value-string

npm install -g key-value-string

After global installation, the kvs command will be available in your terminal.

const { parseKeyValueString, toKeyValueString } = require('key-value-string'); // Parse key-value string const result = parseKeyValueString('name=John;age=30;tags=frontend,backend;'); console.log(result); // { name: 'John', age: 30, tags: ['frontend', 'backend'] } // Convert object to key-value string const kvString = toKeyValueString({ name: 'John', age: 30, active: true }); console.log(kvString); // name=John;age=30;active=true;

import { parseKeyValueString, toKeyValueString } from 'key-value-string'; const parsed = parseKeyValueString('server=localhost;port=3000;debug=true;'); console.log(parsed); // { server: 'localhost', port: 3000, debug: true }

<script src="https://unpkg.com/key-value-string/dist/index.umd.js"></script> <script> const { parseKeyValueString, toKeyValueString } = KeyValueString; const config = parseKeyValueString('theme=dark;fontSize=14;showLineNumbers=true;'); console.log(config); </script>

<script type="module"> import { parseKeyValueString } from 'https://unpkg.com/key-value-string/dist/index.esm.js'; const settings = parseKeyValueString('width=800;height=600;fullscreen=false;'); console.log(settings); </script>

Note: Install globally first with npm install -g key-value-string

# Parse key-value string to JSON kvs parse "name=John;age=30;tags=frontend,backend;" # Convert JSON to key-value string kvs stringify '{"name":"John","age":30,"tags":["frontend","backend"]}' # Validate key-value string syntax kvs validate "name=John;age=30;" # Parse from file kvs parse -f config.kvs # Convert JSON file to key-value string kvs stringify -f data.json # Show help kvs --help

The parser is designed for single-line key-value strings (though multiline works, comments are not supported):

• Key-value pairs: key=value;
• Numbers: Automatically parsed (age=30 → { age: 30 })
• Quoted strings: name="John Doe"; for values with spaces or special characters
• Arrays: tags=frontend,backend; → { tags: ['frontend', 'backend'] }
• Null values: optional=; → { optional: null }
• Empty arrays: tags=,; → { tags: [null] }

Note: Comments (# or //) are not supported. Use for single-line configuration strings, URL parameters, or command-line arguments.

Parses a key-value string into an object.

• input: The key-value string to parse
• Returns: Parsed object
• Throws: Error if the string is malformed

Converts an object to a key-value string.

• obj: The object to convert
• Returns: Key-value string representation

interface KeyValueObject { [key: string]: string | number | null | Array<string | number | null>; }

// Parse application config string const configString = 'host=localhost;port=3000;database="my_app_db";timeout=5000;features=auth,logging,cache;debug=true;'; const config = parseKeyValueString(configString); // Use the config console.log(`Server running on ${config.host}:${config.port}`); // Output: Server running on localhost:3000

// Parse URL-like parameters const params = parseKeyValueString('user=123;action=edit;theme=dark;'); console.log(params); // { user: 123, action: 'edit', theme: 'dark' }

// Convert environment-like variables const env = { NODE_ENV: 'production', PORT: 8080, FEATURES: ['auth', 'ssl', 'cache'] }; const envString = toKeyValueString(env); console.log(envString); // NODE_ENV=production;PORT=8080;FEATURES=auth,ssl,cache;

• UMD build: Supports ES2015+ (IE11+ with polyfills)
• ESM build: Supports ES2020+ (modern browsers)
• CommonJS build: Node.js 14+

MIT

Built with ❤️ and way too much coffee in a single night of pure vibecoding.