Developer Guides & Tool Tutorials
In-depth guides for all 99 free browser-based developer tools — covering what each tool does, how to use it, and real-world use cases. No signup required.
JSON Formatter: How to Beautify and Format JSON Online
Learn how to beautify and format JSON instantly with customizable indentation. Make minified or raw API responses readable in seconds.
JSON Minifier: Compress JSON to Reduce File Size
Minify JSON by stripping all unnecessary whitespace to reduce payload size, improve API performance, and cut bandwidth costs.
JSON Validator: How to Check and Fix JSON Syntax Errors
Validate JSON syntax instantly and get clear, line-specific error messages to quickly find and fix malformed JSON in APIs, configs, and data files.
JSON Diff: How to Compare Two JSON Objects Online
Compare two JSON documents side-by-side and highlight every added, removed, and changed value. Ideal for API versioning and config audits.
JSON to CSV Converter: Export JSON Data to Spreadsheets
Convert JSON arrays to CSV format instantly. Export API data to Excel, Google Sheets, or any database with a single click.
JSON to XML Converter: Transform JSON for SOAP and Legacy APIs
Convert JSON to well-formed XML instantly. Bridge modern REST APIs with SOAP services, legacy systems, and XML-based data pipelines.
JSON to YAML: Convert JSON for Docker, Kubernetes, and CI/CD
Convert JSON to YAML format for Kubernetes manifests, Docker Compose, GitHub Actions, and other config-file-heavy DevOps workflows.
JSON to Table: Visualize JSON Data as an Interactive Table
Render JSON arrays as interactive HTML tables with sorting and filtering. Explore API data visually without writing a single line of code.
JSONPath Tester: Test JSONPath Expressions and Queries Online
Test JSONPath expressions against real JSON data instantly. Debug queries for APIs, test automation, and data extraction pipelines.
JSON Schema Validator: Validate JSON Data Against a Schema
Validate JSON data against a JSON Schema (draft-07) definition. Catch type errors, missing required fields, and constraint violations instantly.
Base64 Encode: How to Encode Text and Files to Base64 Online
Learn how Base64 encoding works, when to use it, and how to encode text or binary data to Base64 strings quickly in your browser.
Base64 Decode: How to Decode Base64 Strings Back to Text
Decode Base64-encoded strings back to plain text or binary data instantly. Perfect for debugging JWTs, API responses, and encoded credentials.
URL Encode: How to Percent-Encode URLs and Query Parameters
Percent-encode URLs and query string parameters so special characters are transmitted safely. Essential for building correct API requests and web links.
URL Decode: How to Decode Percent-Encoded URL Strings
Convert percent-encoded URL strings back to readable text. Ideal for debugging query parameters, redirect URLs, and encoded API endpoints.
HTML Encode: Convert Special Characters to HTML Entities
Convert <, >, &, quotes, and other special characters to safe HTML entities. Essential for preventing XSS vulnerabilities in web applications.
HTML Decode: Convert HTML Entities Back to Characters
Convert HTML entities like <, &, and " back to their original characters. Useful for reading encoded HTML content and template debugging.
Unicode Encode: Convert Text to Unicode Escape Sequences
Convert any text to Unicode escape sequences (\uXXXX format) for safe embedding in source code, JSON, and systems that require ASCII-only strings.
Unicode Decode: Convert Unicode Escape Sequences to Text
Convert \uXXXX Unicode escape sequences back to readable text characters. Perfect for reading escaped source code, JSON, and internationalised strings.
JWT Decoder: How to Decode and Inspect JWT Tokens Online
Decode and inspect JWT tokens to view headers, claims, and expiry instantly. Understand token structure without sending tokens to external servers.
JWT Encoder: How to Create and Sign JWT Tokens with HS256
Build and sign JWT tokens with HS256 using browser-native Web Crypto API. Set custom claims, expiry, and issuer without any server or library.
Binary Converter: Convert Text and Numbers to Binary Online
Convert text strings and decimal numbers to binary (base-2) representation and back. Includes ASCII, UTF-8, and multi-base number conversion.
Text Diff Checker: How to Compare Two Text Documents Online
Instantly compare two text blocks side-by-side. Highlight additions, deletions, and changes line-by-line without installing any software.
Remove Duplicate Lines: Clean Up Lists and Text Data Online
Remove duplicate lines from any list or text file instantly. Supports case-sensitive and case-insensitive matching with optional sorting.
Sort Lines Online: Alphabetical, Numerical, and Custom Text Sorting
Sort any list of lines alphabetically, numerically, by length, or randomly. Supports ascending and descending order with case options.
Reverse Text Online: Flip Characters or Words in Any String
Reverse any text string instantly. Flip individual characters, reverse word order, or mirror each line independently with a single click.
Word Counter: Count Words, Characters, and Estimate Reading Time
Count words, characters, sentences, and paragraphs in any text. Get an instant reading time estimate and detailed text statistics.
Character Counter: Count Characters and Analyze Text Frequency
Count total characters with and without spaces, and see a full character frequency distribution for any text input instantly.
Case Converter: Convert Text to camelCase, snake_case, Title Case and More
Convert text between UPPERCASE, lowercase, Title Case, camelCase, PascalCase, snake_case, and kebab-case instantly online.
Slug Generator: Create SEO-Friendly URL Slugs from Any Text
Convert any title or phrase into a clean, SEO-friendly URL slug. Handles accented characters, special symbols, and multiple languages.
Text to ASCII Art Generator: Create ASCII Banners Online
Convert any text to figlet-style ASCII art banners. Choose from multiple fonts to create terminal headers, README banners, and text logos.
Lorem Ipsum Generator: Create Placeholder Text for Mockups
Generate classic lorem ipsum placeholder text by words, sentences, or paragraphs. Perfect for UI mockups, wireframes, and layout testing.
Markdown to HTML Converter: Convert Markdown Syntax to HTML Online
Instantly convert Markdown syntax to clean HTML. Supports headings, lists, links, images, code blocks, tables, and GitHub Flavored Markdown.
HTML to Markdown: Convert HTML to Clean Markdown Text Online
Convert HTML markup to clean, readable Markdown syntax. Ideal for migrating web content to Markdown-based CMSs, wikis, and documentation tools.
Email Validator: Check Email Address Format and Syntax Online
Validate email address format and syntax instantly. Check for RFC 5322 compliance, common typos, and disposable domain detection.
CSV to JSON Converter: Import CSV Data into JavaScript Applications
Convert CSV spreadsheet data into JSON arrays instantly. Supports custom delimiters, quoted fields, and header row detection for seamless JavaScript integration.
CSV Formatter: Clean and Reformat Messy CSV Files Online
Normalize inconsistent CSV files by fixing spacing, quoting, and delimiters. Produce clean, RFC 4180-compliant output ready for import into any data tool.
XML Formatter: Beautify and Indent XML Documents Online
Pretty-print minified or poorly indented XML documents with consistent indentation and line breaks. Instant browser-based formatting with no server upload required.
XML Validator: Check XML Syntax and Validate Well-Formedness
Validate XML documents for well-formedness instantly in your browser. Detailed error messages include line numbers, column positions, and clear descriptions to fix issues fast.
XML to JSON Converter: Parse XML Documents to JSON Online
Convert XML documents to JSON with configurable attribute handling, text node mapping, and array coercion. Perfect for consuming XML APIs in JavaScript applications.
YAML Formatter: Format and Validate YAML Configuration Files
Parse and re-serialize YAML configuration files with consistent indentation and style. Catches syntax errors instantly and normalizes mixed-style YAML into clean output.
YAML to JSON Converter: Convert YAML Config Files to JSON
Convert YAML configuration files to JSON, with full support for anchors, aliases, multi-document files, and all YAML 1.2 data types. Instant browser-based conversion.
TOML to JSON Converter: Parse Cargo.toml and Config Files
Convert TOML configuration files to JSON online. Supports all TOML v1.0 features including tables, arrays of tables, inline tables, and datetime values.
SQL Formatter: Beautify SQL Queries for MySQL, PostgreSQL, and More
Format messy SQL queries with capitalized keywords, consistent indentation, and aligned clauses. Supports MySQL, PostgreSQL, SQLite, T-SQL, and standard ANSI SQL.
SQL Minifier: Compress SQL Queries by Removing Whitespace
Strip whitespace, newlines, and comments from SQL queries to produce compact, single-line output. Useful for embedding SQL in APIs, config files, and environment variables.
Password Generator: Create Cryptographically Secure Passwords Online
Generate strong, random passwords using the Web Crypto API. Customize length, character sets, and rules to meet any security policy.
Password Strength Checker: How to Evaluate and Improve Your Password
Instantly check your password strength with scoring based on length, character variety, patterns, and known dictionary words — all client-side.
Hash Generator: Create MD5, SHA-256, and SHA-512 Hashes Online
Generate MD5, SHA-1, SHA-256, and SHA-512 hashes instantly from text or files using the Web Crypto API — entirely in your browser.
Hash Compare: Verify File and Data Integrity by Comparing Hashes
Compare two hash strings side by side with constant-time comparison to verify file integrity, detect tampering, and validate checksums.
HMAC Generator: Create HMAC-SHA256 and HMAC-SHA512 Signatures Online
Generate HMAC-SHA256 and HMAC-SHA512 signatures for API authentication and data integrity verification — computed entirely in your browser.
UUID Generator: Create RFC 4122 Compliant UUIDs (v4) Online
Generate cryptographically random UUID v4 values compliant with RFC 4122 — instantly and entirely in your browser using the Web Crypto API.
Random Token Generator: Create Secure Hex and Base64 Tokens
Generate cryptographically secure random tokens in hex or Base64 encoding for API keys, session IDs, secrets, and CSRF tokens — client-side only.
RSA Key Pair Generator: Create RSA Public and Private Keys Online
Generate RSA 2048-bit and 4096-bit public/private key pairs using the Web Crypto API — entirely in your browser, with no server involvement.
OTP Generator: Generate TOTP and HOTP One-Time Passwords Online
Generate RFC 6238 TOTP and RFC 4226 HOTP one-time passwords for testing and development of two-factor authentication systems.
HTTP Status Codes: Complete Reference Guide for Developers
A complete reference for all HTTP status codes from 1xx to 5xx — what they mean, when they occur, and how to handle them in your applications.
Query String Parser: Decode and Inspect URL Query Parameters
Instantly parse any URL query string into readable key-value pairs. Decode percent-encoded characters and inspect parameters one by one.
Query String Builder: Build URL Query Strings from Key-Value Pairs
Construct valid, properly encoded URL query strings from key-value pairs. Add, edit, and remove parameters with instant URL preview.
cURL to Code Converter: Convert cURL Commands to JavaScript, Python and More
Paste any cURL command and instantly convert it to JavaScript fetch, Python requests, Node.js, PHP, Go, or other languages.
Color Picker: Get HEX, RGB, and HSL Values for Any Color
Pick any color visually and instantly get its HEX, RGB, HSL, and HSB values. Copy color codes for use in CSS, design tools, or code.
HTTP Header Parser: Analyze Request and Response Headers Online
Paste raw HTTP request or response headers and instantly parse them into a clean key-value table for easy inspection and debugging.
URL Parser: Break Down URLs into Protocol, Host, Path, and Query
Decompose any URL into its individual components — protocol, hostname, port, path, query string, and fragment — for easy inspection.
Basic Auth Generator: Create HTTP Basic Authentication Headers
Generate Base64-encoded HTTP Basic Authentication header values from a username and password. Copy the Authorization header value instantly.
MIME Type Lookup: Find the Content-Type for Any File Extension
Look up the correct MIME type (Content-Type) for any file extension. Find the right value for HTTP headers, server configuration, and APIs.
Meta Tag Generator: Create HTML Meta Tags for SEO and Social Sharing
Generate complete HTML meta tags for SEO, Open Graph (Facebook), and Twitter Cards. Fill in the fields and copy the ready-to-use HTML.
Regex Tester: Test Regular Expressions with Live Match Highlighting
Test and debug regular expressions instantly with live match highlighting, group capture display, and full flag controls in your browser.
Regex Generator: Generate Regular Expression Patterns from Examples
Generate accurate regular expression patterns from plain English descriptions or input/output examples without memorizing regex syntax.
Regex Cheatsheet: Complete Regular Expression Quick Reference Guide
A complete, searchable regex cheatsheet covering anchors, quantifiers, character classes, groups, lookaheads, and flags with live examples.
Regex Explainer: Understand What Any Regular Expression Does in Plain English
Paste any regular expression and get an instant plain-English explanation of every component, token, and flag — no regex knowledge required.
Unix Timestamp Converter: Convert Timestamps to Human-Readable Dates
Convert Unix timestamps to readable dates and times — and any date back to a Unix timestamp — instantly with timezone support.
Date Difference Calculator: Find Days, Hours, and Minutes Between Dates
Calculate the exact difference between any two dates in years, months, weeks, days, hours, minutes, and seconds — with DST awareness.
Timezone Converter: Convert Times Between Any Two Timezones
Instantly convert times between any two of 400+ timezones worldwide, with DST indicators, UTC offsets, and shareable result URLs.
Relative Timestamp: Convert Dates to Relative Time Strings Like "3 Days Ago"
Convert any date or Unix timestamp into a natural relative time string like "3 hours ago" or "in 2 weeks" — with locale and threshold controls.
QR Code Generator: Create QR Codes from Text or URLs Online
Generate QR codes instantly from any text, URL, or data string. Download as PNG for print or digital use — no sign-up required.
Cron Expression Generator: Build and Understand Cron Job Schedules
Build valid cron expressions using a visual interface. Get plain-English descriptions, next-run previews, and copy-ready syntax for any scheduler.
Markdown Preview: Live-Preview Markdown as Rendered HTML
Write Markdown in the left pane and see the rendered HTML output instantly on the right. Supports GFM, tables, code blocks, and inline HTML.
Image to Base64: Convert Images to Base64 Data URIs Online
Convert PNG, JPG, GIF, SVG, and WebP images to Base64 data URIs for embedding directly in HTML, CSS, or JavaScript — no file requests needed.
SVG Optimizer: Clean and Compress SVG Files Online
Remove unnecessary attributes, comments, metadata, and redundant paths from SVG files. Reduce SVG file size without changing visual output.
CSS Minifier: Compress CSS Files by Removing Whitespace and Comments
Minify CSS by stripping whitespace, comments, and redundant code. Reduce CSS payload size for faster page loads without changing any styles.
JavaScript Formatter: Beautify and Format JavaScript Code Online
Paste minified or messy JavaScript and get back properly indented, readable code. Supports modern JS, TypeScript syntax, and configurable indent size.
chmod Calculator: Calculate Unix File Permission Values Online
Calculate Unix chmod permission values by clicking checkboxes for owner, group, and other. Get the octal code and the chmod command instantly.
.gitignore Builder: Generate .gitignore Files for Any Language or Framework
Select your languages, frameworks, and tools to generate a complete .gitignore file. Combines entries from multiple sources into one clean, ready-to-use file.
Favicon Generator: Create Favicons in Multiple Sizes from Any Image
Upload any image and generate favicons in 16x16, 32x32, 48x48, and 64x64 sizes. Download as PNG files ready to add to your website head.
Docker Compose Generator: Generate Docker Compose YAML for Common Services
Select services like Postgres, Redis, Nginx, and MongoDB to generate a ready-to-use Docker Compose YAML file with volumes, networks, and environment variables.
Conventional Commit Helper: Build Properly Formatted Commit Messages
Build commit messages following the Conventional Commits specification. Select type, scope, and write a description to generate a perfectly formatted message.
CSS Gradient Generator: Create Linear and Radial Gradients Online
Build CSS linear and radial gradients visually with a live preview, color stop controls, and instant copy-ready CSS output.
Box Shadow Generator: Build CSS Box Shadow Values Visually
Create CSS box-shadow values visually with controls for offset, blur, spread, color, opacity, and inset — with multi-layer shadow support.
Border Radius Generator: Create CSS Border Radius Values Online
Create CSS border-radius values visually — from simple rounded corners to complex elliptical and asymmetric shapes — with instant code output.
CSS Grid Generator: Build CSS Grid Layouts with a Visual Editor
Design CSS Grid layouts visually — define rows, columns, gaps, and item placement — and export clean, production-ready CSS code.
Flexbox Generator: Create CSS Flexbox Properties Visually
Build CSS Flexbox container and item properties visually with live preview, all flex properties supported, and copy-ready CSS output.
CSS Unit Converter: Convert Between px, rem, em, vw, and More
Convert CSS units between px, rem, em, vw, vh, pt, and cm instantly with configurable base font size and viewport dimensions.
CSS Specificity Calculator: Calculate the Specificity of Any CSS Selector
Calculate the specificity score of any CSS selector instantly, understand why your styles are being overridden, and compare multiple selectors side by side.
Base Converter: Convert Numbers Between Binary, Octal, Decimal, and Hex
Convert numbers between binary, octal, decimal, and hexadecimal instantly. Free online base converter — no signup, runs in your browser.
Percentage Calculator: Calculate Percentages and Percentage Change Online
Calculate percentages, percentage change, and reverse percentages instantly. Free online percentage calculator — no signup required.
Temperature Converter: Convert Between Celsius, Fahrenheit, and Kelvin
Convert temperatures between Celsius, Fahrenheit, and Kelvin instantly. Free online temperature converter — no signup, runs in your browser.
Number to Words: Convert Numbers to Their English Word Representation
Convert any number to its English word representation instantly. Perfect for check writing, legal documents, and accessibility. Free online tool.
Number Formatter: Format Numbers with Commas, Decimals, and Locale Settings
Format numbers with thousand separators, decimal places, and locale-aware styles. Free online number formatter — no signup required.
Aspect Ratio Calculator: Calculate and Convert Image and Video Aspect Ratios
Calculate aspect ratios for images and video, find dimensions that maintain a ratio, and convert between common formats. Free online tool.
IPv4 Subnet Calculator: Calculate Network Address, Mask, and Host Range
Calculate subnet masks, network addresses, broadcast addresses, and usable host ranges instantly using CIDR notation for network planning.
MAC Address Generator: Generate Random and Vendor-Prefixed MAC Addresses
Generate random or vendor-prefixed MAC addresses for VMs, network testing, simulation environments, and hardware spoofing scenarios instantly.
IPv4 Address Converter: Convert IP Addresses Between Decimal, Binary, and Hex
Convert IPv4 addresses between dotted decimal, binary, hexadecimal, and 32-bit integer formats for networking courses, firewall config, and packet analysis.