Free Online Developer Tools

Essential developer utilities that work instantly in your browser. Format JSON, test regex, generate UUIDs, decode JWTs, and more — no installation required.

JSON Formatter & Validator

Format, beautify, and validate JSON data online. Instantly indent and syntax-highlight your JSON with error detection.

Pretty-print with customizable indentationSyntax validation with error line numbers

JSON to CSV Converter

Convert JSON arrays to CSV format instantly. Transform JSON data into downloadable spreadsheet-compatible CSV files.

Automatic column header detectionHandles nested objects with dot notation

CSV to JSON Converter

Convert CSV data to JSON format online. Transform spreadsheet CSV files into structured JSON arrays instantly.

Auto-detect headers from first rowSupport for comma, tab, and semicolon delimiters

HTML Formatter & Beautifier

Format and beautify HTML code with proper indentation. Clean up messy HTML markup instantly with this free tool.

Auto-indent nested HTML elementsCustomizable indentation size

CSS Minifier

Minify CSS code to reduce file size. Remove comments, whitespace, and optimize selectors for faster page loads.

Removes comments and unnecessary whitespaceShortens color values like #ffffff to #fff

CSS Formatter & Beautifier

Format and beautify CSS code with proper indentation. Make minified or messy CSS readable and well-structured.

Proper indentation for nested rulesOne property per line formatting

JavaScript Minifier

Minify JavaScript code to reduce file size. Remove whitespace, shorten variables, and optimize for production use.

Removes whitespace and commentsShortens local variable names

JavaScript Beautifier

Beautify and format JavaScript code with proper indentation. Make minified JS readable with customizable formatting.

Smart indentation for all JS structuresCustomizable indent size and style

SQL Formatter

Format and beautify SQL queries with proper indentation. Support for MySQL, PostgreSQL, SQL Server, and more.

Keywords in uppercase formattingProper indentation for subqueries

XML Formatter & Validator

Format, beautify, and validate XML documents. Indent nested elements and detect syntax errors in XML data.

Pretty-print with customizable indentationWell-formedness validation with error reporting

Regex Tester

Test and debug regular expressions in real time. Match, capture, and replace with live highlighting and explanations.

Real-time match highlightingCapture group identification

Color Picker & Converter

Pick colors and convert between HEX, RGB, HSL, and CMYK formats. Generate color palettes and gradients online.

Visual color picker with gradient selectorConvert between HEX, RGB, HSL, HSV, and CMYK

Base64 Image Encoder

Convert images to Base64 encoded strings and data URIs. Embed images directly in HTML and CSS without external files.

Drag and drop image uploadGenerates data URI with correct MIME type

Markdown to HTML Converter

Convert Markdown to clean HTML code instantly. Transform MD syntax to valid HTML with live preview and syntax highlighting.

Full GitHub Flavored Markdown supportLive rendered preview alongside HTML output

HTML to Markdown Converter

Convert HTML code to clean Markdown syntax. Transform web content into Markdown format for docs and READMEs.

Converts all common HTML elements to MarkdownHandles tables, lists, and code blocks

JWT Decoder

Decode and inspect JSON Web Tokens. View the header, payload, and signature of any JWT without a secret key.

Decodes header and payload instantlyDisplays claim names with descriptions

UUID Generator

Generate random UUIDs (v4) and other UUID versions online. Create unique identifiers for databases and applications.

Generate UUID v1, v4, and v5Bulk generation of multiple UUIDs

Hash Generator (MD5, SHA1, SHA256)

Generate MD5, SHA-1, SHA-256, and SHA-512 hashes from text. Create cryptographic hash values for verification and security.

MD5, SHA-1, SHA-256, and SHA-512 algorithmsReal-time hashing as you type

Unix Timestamp Converter

Convert Unix timestamps to human-readable dates and vice versa. Support for seconds, milliseconds, and multiple formats.

Convert timestamp to date and date to timestampSupport for seconds and milliseconds precision

Cron Expression Parser

Parse and explain cron expressions in plain English. Build, validate, and test cron schedules with a visual editor.

Plain English description of any cron expressionVisual cron builder with dropdowns

IP Address Lookup

Look up details about any IP address including geolocation, ISP, and network information. Find your own public IP address.

Shows your current public IP addressGeolocation with country, city, and region

HTTP Status Code Reference

Browse all HTTP status codes with descriptions and examples. Understand 1xx to 5xx response codes for web development.

Complete list of all HTTP status codesDetailed description for each code

HTML Entity Encoder/Decoder

Encode special characters to HTML entities and decode entities back to characters. Essential for safe HTML output.

Encode special characters to named and numeric entitiesDecode HTML entities back to characters

URL Parser & Encoder

Parse URLs into components and encode/decode URL strings. Analyze protocol, host, path, query parameters, and fragments.

Parse URL into protocol, host, path, query, and fragmentURL encode and decode strings

Code Diff Tool

Compare two code files side by side with syntax highlighting. Find differences in source code with line-level precision.

Side-by-side and unified diff viewsSyntax highlighting for 50+ languages

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Free Online Developer Tools - JSON Formatter, Regex Tester & More | WebToolsMagic