Developer Tools
Essential utilities for developers. Format, encode, decode, and generate.
Free developer utilities for the small jobs that interrupt real work: formatting a wall of minified JSON, decoding a JWT, generating a UUID, checking what a cron expression actually means. Everything runs client-side, so you can paste a payload without wondering where it went.
Formatters & Validators
JSON Formatter
Format, validate, and beautify JSON data
XML Formatter
Format, beautify, and validate XML documents
SQL Formatter
Format and beautify SQL queries for MySQL, PostgreSQL, SQL Server, and more
YAML Validator
Validate, format, and convert YAML files
Code Beautifier
Format and beautify JavaScript, CSS, and HTML code
Code Minifier
Minify JavaScript, CSS, and HTML code to reduce file size
Markdown Editor
Write and preview Markdown with live rendering and formatting tools
Code Diff
Compare and highlight differences between two code snippets
Encoders & Converters
Base64 Encoder/Decoder
Encode and decode Base64 strings
URL Encoder/Decoder
Encode and decode URL strings
HTML Entity Encoder/Decoder
Encode and decode HTML entities for special characters
Image to Base64
Convert images to Base64 encoded strings for embedding in code
JSON ↔ CSV Converter
Convert between JSON and CSV formats with options for nested data
JSON ↔ YAML Converter
Convert between JSON and YAML formats with bidirectional conversion
SQL to NoSQL Converter
Convert SQL CREATE TABLE and SELECT statements to MongoDB, DynamoDB, Firebase, and CouchDB
Number Base Converter
Convert numbers between binary, decimal, hexadecimal, and octal
Unix Timestamp Converter
Convert between Unix timestamps and human-readable dates
Roman Numeral Converter
Convert between Arabic numbers and Roman numerals
Number to Words Converter
Convert numbers to written words for checks and documents
Generators
UUID Generator
Generate unique UUIDs (v4) instantly
Hash Generator
Generate MD5, SHA-1, SHA-256, and SHA-512 hashes
Password Generator
Generate strong, secure passwords with customizable options
QR Code Generator
Create custom QR codes for URLs, text, email, phone, and SMS
WiFi QR Code Generator
Create a QR code for instant WiFi network access
Barcode Generator
Generate UPC, EAN, Code 128, QR codes and more
Favicon Generator
Create favicons in all sizes from images or text/emoji
Fake Data Generator
Generate realistic test data like names, emails, addresses, and more
Cron Generator
Build and validate cron expressions with visual editor
Lorem Ipsum for Code
Generate realistic placeholder code snippets in 12 programming languages
Markdown Table Generator
Create Markdown tables with a visual editor. Import CSV, JSON, or Markdown and export in multiple formats
HTML Table Generator
Create accessible HTML tables with a visual editor. Import data, apply styling themes, and export with proper semantic markup
JSON Schema Generator
Generate JSON Schema from sample JSON data. Validate JSON against schemas with detailed error reporting
Changelog Generator
Create professional changelogs in Keep a Changelog format with semantic versioning support
Testing & Debugging
Regex Tester
Test and debug regular expressions with real-time matching and highlighting
JWT Decoder
Decode and inspect JSON Web Tokens with claim explanations
API Request Builder
Test APIs with a powerful HTTP client. Supports all methods, auth, headers, and code generation
HTTP Status Code Lookup
Search and reference every HTTP status code with meanings and descriptions
Subnet Calculator
Calculate IPv4 subnet masks, network addresses, broadcast addresses, and host ranges
Chmod Calculator
Calculate Unix file permissions in octal and symbolic notation
Web & SEO
Browser & Network
More tools
HMAC Generator
Generate and verify HMAC signatures with SHA-1, SHA-256, SHA-384, or SHA-512
Query String Parser & Builder
Parse a URL or query string into key-value pairs and rebuild a clean, encoded query
Curl to Code Converter
Turn a curl command into fetch, axios, Python, PHP, Go or Java code
HTML to JSX Converter
Convert HTML into valid JSX for React or Preact, attributes and styles included
.gitignore Generator
Build a .gitignore from language, framework, editor and OS templates
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