Developer
Essential developer tools: JSON formatter, regex tester, UUID generator, Base64 encoder, Markdown preview, CSS/HTML/JS utilities, and more. All tools run in your browser โ no data leaves your machine.
36 free tools
JSON/YAML Converter
Convert between JSON and YAML formats.
JSON Difference Checker
Compare two JSON strings and find differences
JSON to CSV Converter
Convert JSON arrays of objects to CSV format. Download or copy the result.
CSV to JSON Converter
Convert CSV data to JSON array of objects. First row is used as headers.
CSS Formatter
Format, beautify, and minify CSS code. Free, fast, no sign-up.
CSS Minifier
Minify CSS code to reduce file size. Removes whitespace and comments.
CSS Units Converter
Convert between px, rem, em, vw, vh, % CSS units.
HTML Formatter
Format, minify, and beautify HTML code with configurable indentation.
JavaScript Formatter & Minifier
Format, beautify, and minify JavaScript code.
SQL Formatter
Format, beautify, and minify SQL queries. Free, fast, no sign-up.
XML Formatter
Format, beautify, and minify XML documents. Free, fast, no sign-up.
YAML Formatter
Format, beautify, and validate YAML files. Free, fast, no sign-up.
Regex Tester
Test regular expressions against text. See all matches instantly.
Cron Expression Generator
Visually build cron schedule expressions. See human-readable descriptions.
MIME Types Lookup
Search and lookup common MIME types by file extension.
HTTP Status Codes
Complete reference of HTTP status codes from 1xx to 5xx.
URL Encoder/Decoder
Encode or decode URL components with percent-encoding (UTF-8).
URL Slug Generator
Generate SEO-friendly URL slugs from any text.
UUID Generator
Generate cryptographically secure UUID v4 identifiers. Batch generate up to 100.
JWT Decoder
Decode JSON Web Tokens to view Header and Payload. No verification.
HTML Entities Encoder/Decoder
Encode special characters to HTML entities or decode them back.
Chmod Calculator
Calculate Unix file permissions. Convert between octal and symbolic notation.
String Escape/Unescape
Escape and unescape special characters for JavaScript, HTML, and URLs.
String Similarity
Compare two strings and calculate Levenshtein distance and similarity percentage.
CSV to Markdown Table
Convert CSV data to Markdown table format.
Markdown Table Generator
Visual table builder for Markdown tables. Add rows, columns, and alignment.
Meta Tag Generator
Generate SEO-friendly meta tags for your website
WCAG Color Contrast Checker
Check color contrast ratios against WCAG 2.1 AA and AAA standards.
CSS Box Shadow Generator
Visually create CSS box shadows with live preview
Bitwise Calculator
Perform bitwise operations (AND, OR, XOR, NOT, Shift) on numbers.
ABI Encoder/Decoder
Encode and decode Ethereum ABI function signatures with function selectors
Keccak-256 Hash Generator
Compute Keccak-256 hashes for text or hex data, with function selector and address extraction
Block Explorer Link Generator
Generate block explorer links for Ethereum, BSC, Polygon, and other EVM chains
Favicon Generator
Generate favicons in all sizes from any image. Download as ZIP with manifest and HTML links.
App Icon Generator
Generate app icons for iOS, Android, Web, macOS, and Windows in all required sizes. Download as ZIP.
Hex UTF-8 Base64 Converter
Convert between Hex, UTF-8 text, and Base64 encodings.
Which tool should you use?
Essential utilities for web developers, data engineers, and API integrators. All tools run entirely in your browser โ no data is sent to any server.
JSON Formatter for JSON data, YAML Formatter for YAML configs, and XML Formatter for XML documents. Choose based on the data format you are working with.
Regex Tester validates and debugs regular expressions. Base64 Encoder/Decoder converts data to/from Base64. UUID Generator creates unique identifiers for databases and APIs.
SQL Formatter beautifies database queries. HTML and CSS Formatters clean up markup and stylesheets. Essential for code reviews and documentation.