Developer Tools

Essential tools for developers: code formatters, diff checkers, regex testers, API tools, and debugging utilities for efficient development workflow.

100 tools available

AI Tools 1

Prompt Token Budget Planner

Estimate token usage for Claude, GPT, Gemini, Llama and split long prompts into model-safe chunks with overlap. Free, offline, no API key needed.

Audio Tools 1

Text to Speech

Convert text to speech free in your browser. Pick from dozens of voices, adjust rate, pitch, volume. 100% private, no upload. Works in any modern browser.

Blockchain Tools 5

Blockchain Timestamp Converter

Convert Unix timestamps to human dates and vice versa for Ethereum, Bitcoin, Solana and EVM chains. Solidity-friendly, smart contract debugging.

Keccak SHA3 Hasher

Generate Keccak-256, Keccak-512, SHA3-256, SHA3-512 hashes online. Free Ethereum-compatible hash tool for smart contracts and blockchain development.

ABI Encoder / Decoder

Encode function calls into calldata or decode raw transaction input data for Ethereum, Polygon, BSC and any EVM chain. Supports tuples, arrays, structs.

EVM Transaction Decoder

Decode EVM raw transaction hex for Ethereum, BSC, Polygon, Arbitrum, Optimism, Avalanche. View transaction details, gas, value, data, and signatures.

Solidity Function Selector

Generate Solidity function selectors and event Topic0 hashes from signatures. Encode 4-byte selectors, lookup common ERC20 and DeFi signatures.

Calculators 1

Math Calculators 1

Binary calculator

Binary calculator: add, subtract, multiply, divide, AND, OR, XOR, NOT, shift. BigNumber support, base conversion, two's complement explained.

Color Tools 7

Border Radius Generator

Generate CSS border-radius for rounded corners and organic blob shapes. Simple, advanced and blob modes with 12 presets. Live preview, copy CSS instantly.

Glassmorphism Generator

Create modern frosted glass UI effects with CSS backdrop-filter. Adjust blur, transparency, borders. 6 presets, live preview, copy production-ready code.

Flexbox Generator

Free CSS Flexbox generator and playground. Learn flexbox visually with live preview. Adjust container and item properties, export CSS code. Perfect for learning and creating layouts.

Box Shadow Generator

Free CSS box-shadow generator. Create beautiful shadows with live preview. Adjust blur, spread, offset, opacity, multiple layers. Copy ready-to-use CSS code.

CSS Animation

Build CSS @keyframes animations visually. 11 presets, live preview, editable keyframe table, transform + opacity + color, copy production-ready CSS.

Clamp() Calculator

Free CSS clamp() calculator for fluid typography and responsive sizing. Set min/max viewport and min/max sizes — get a ready-to-paste clamp() with live preview at any width.

Cubic Bezier Editor

Free visual cubic-bezier editor for CSS animations. Drag handles to design custom easing curves, preview the animation live, and copy the cubic-bezier() value instantly.

Data Tools 5

Schema Extractor

Generate TypeScript interfaces, JSON Schema, Go structs from JSON or CSV. Extract data schemas automatically. Free online tool.

YAML-JSON Converter

Convert YAML to JSON and JSON to YAML instantly. Free online tool with formatting options. Process data securely in your browser.

Free online JSON tree viewer and visualizer. Explore JSON data with interactive collapsible tree structure, syntax highlighting, search, and fullscreen mode. Perfect for analyzing complex JSON APIs, debugging nested data, and understanding JSON structures.

CSV-SQL Converter

Convert CSV to SQL INSERT, CREATE TABLE statements or back to CSV in your browser. Auto-detect data types, custom delimiters, MySQL Postgres SQLite friendly.

XML-JSON Converter

Convert between XML and JSON formats instantly. Free bidirectional converter supporting custom formatting, attributes, and nested structures.

Developer Tools 66

Encoding 17

Base32 Encoder/Decoder

Encode text to Base32 or decode it back instantly per RFC 4648. Optional padding, case-insensitive input. Ideal for 2FA secrets, QR codes and DNS.

Base58 Encoder/Decoder

Free online Base58 encoder and decoder tool. Encode text to Base58 or decode Base58 to text instantly. Uses Bitcoin alphabet without confusing characters (0, O, I, l). Perfect for developers working with cryptocurrencies, blockchain, Bitcoin addresses, and human-readable encoding.

Base64 Encoder/Decoder

Free online Base64 encoder and decoder tool. Encode text to Base64 or decode Base64 to text instantly. Supports UTF-8, ASCII, URL-safe encoding and multiple character sets. Perfect for developers working with APIs, data encoding, and web development.

Base85 Encoder/Decoder

Encode text or binary to Base85 (Ascii85) and decode back instantly. 25% more compact than Base64, perfect for PDF, PostScript and Git pack files.

Bcrypt Hash Generator

Generate bcrypt password hashes online with adjustable cost factor (4–14 rounds). Verify existing $2a, $2b, $2y hashes. Standard for secure auth systems.

HMAC Generator

HMAC-SHA256/SHA-512/SHA-1 generator — sign webhooks, AWS requests, JWT HS256 tokens. Hex or Base64 output. WebCrypto, 100% browser.

HTML Entities Encoder/Decoder

Encode special characters to HTML entities or decode them back. Named (&), numeric (&) and hex (&) forms. Prevent XSS and display HTML safely.

Hex Encoder/Decoder

Text ⇄ hex converter — plain, 0x-prefixed, space-separated, upper/lowercase. Auto-detects on decode, handles UTF-8. For debugging, memory dumps, colors.

Image Base64 Encoder/Decoder

Encode images to Base64 data URLs or decode Base64 back to images. Supports PNG, JPG, GIF, WebP, BMP, SVG with HTML/CSS-ready output formats.

JWT Encoder/Decoder

Free online JWT (JSON Web Token) encoder and decoder tool. Create JWT tokens or decode and analyze existing tokens instantly. View header, payload, signature, and claims information. Supports HMAC algorithms (HS256, HS384, HS512). Perfect for developers working with authentication, OAuth, and API security.

MD5 Hash Generator

Free online MD5 hash generator and MD5 encrypt tool. Generate MD5 hash from text instantly. Create 128-bit MD5 checksums for data integrity verification, file comparison, and development testing. Perfect for developers needing quick MD5 hash generation.

Morse Code Translator

Translate text to international Morse code and back with audio playback. Adjustable WPM, customisable separator, interactive chart. SOS-friendly.

Punycode Converter

Convert Unicode domain names (IDN) to ASCII Punycode and back, per RFC 3492. Supports all scripts: Latin diacritics, Chinese, Cyrillic, Arabic.

SHA-1 Hash Generator

Free online SHA-1 hash generator and SHA-1 encrypt tool. Generate SHA-1 hash from text instantly. Create 160-bit SHA-1 checksums for data integrity verification and development. Fast, client-side SHA-1 hashing.

SHA-256 Hash Generator

Free online SHA-256 hash generator and SHA-256 encrypt tool. Generate SHA-256 hash from text instantly. Create 256-bit SHA-256 checksums for blockchain, Bitcoin, SSL certificates, and secure data integrity. Industry-standard cryptographic hash function.

SHA-512 Hash Generator

Free SHA-512 hash generator. Compute 128-character checksums from any text using the Web Crypto API — runs 100% in your browser, nothing uploaded.

URL Encoder/Decoder

Free online URL encoder and decoder tool. Encode text for URLs or decode URL-encoded strings instantly. Convert special characters, spaces, and Unicode to percent-encoded format. Perfect for web developers working with query parameters, API endpoints, and URL handling.

Formatter & Minifier 10

CSS Formatter & Minifier

Free online CSS formatter and beautifier. Format, beautify, and minify CSS code with syntax highlighting. Perfect for web developers and designers working with stylesheets.

HTML Formatter & Minifier

Free online HTML formatter and beautifier. Format, beautify, and minify HTML code with syntax highlighting. Perfect for web developers and designers working with HTML markup.

JSON Formatter & Minifier

Free online JSON formatter and validator. Format, beautify, minify, and validate JSON data with syntax highlighting. Perfect for developers working with JSON APIs, configuration files, and data structures.

JavaScript Formatter & Minifier

Free online JavaScript formatter, beautifier and minifier with syntax highlighting and configurable indent. Supports ES6+, arrow functions, async/await.

Markdown Formatter

Format, beautify and preview Markdown online. Normalises headings, list markers, spacing and code blocks. Live HTML preview, GitHub-flavoured support.

PHP Formatter & Minifier

Free online PHP formatter and beautifier. Format, beautify, and minify PHP code with syntax highlighting. Perfect for PHP developers working with server-side scripts.

Python Formatter & Minifier

Free online Python formatter, beautifier and minifier with PEP 8 indentation, blank-line normalisation and syntax highlighting. Type-hint aware.

SQL Formatter & Minifier

Format, beautify and minify SQL queries with syntax highlighting and uppercase keywords. Works with MySQL, PostgreSQL, SQL Server, Oracle and SQLite.

XML Formatter & Minifier

Free online XML formatter and validator. Format, beautify, minify, and validate XML data with syntax highlighting. Perfect for developers working with XML files, APIs, and configuration.

YAML Formatter & Minifier

Free online YAML formatter and beautifier. Format, beautify, and minify YAML code with syntax highlighting. Perfect for developers working with YAML configuration files and data structures.

Generators 14

Redirection Rules Generator

Build redirect rules for Apache .htaccess, Nginx, Netlify _redirects — 301/302/307/308. Bulk import, sample data, syntax-correct output for migrations.

TOTP Generator

Free online TOTP / 2FA code generator (RFC 6238). Paste a Base32 secret to see the current and next codes, scan the QR with Google Authenticator, and verify your setup.

.htaccess Generator

Generate Apache .htaccess online: force HTTPS, redirect WWW, enable GZIP, set caching, block bots, add security headers, custom redirects and error pages.

Cron Expression Generator

Build, validate and preview Cron expressions for Linux and Quartz. Visual fields, human-readable description and next run times. Free, no signup.

Favicon Generator

Generate favicon files in all required sizes and formats for your website. Create ICO, PNG, and Apple Touch icons from a single image. Free online favicon maker.

JSON-LD Generator

Generate Google-friendly Schema.org JSON-LD markup for FAQ, Article, LocalBusiness, Product, Recipe, Event, Breadcrumb, Organization, Person, Video, HowTo, Review.

Manifest Generator

Create a Web App Manifest (manifest.json) for Progressive Web Apps: name, icons, theme color, display mode, orientation, shortcuts. Standards-compliant.

Meta Tag Generator

Generate HTML meta tags for SEO, Open Graph and Twitter Cards. Title, description, canonical, robots, OG image, social preview — copy-ready HTML.

Regex Generator

Visual regex builder + live tester. 12 prebuilt patterns (email, URL, IPv4, credit card, ISO date), generates JS/Python/PHP/Java/Ruby/Go code.

Robots.txt Generator

Free robots.txt generator tool. Create, test and validate robots.txt file for your website. Control search engine crawlers with easy-to-use interface. SEO optimization tool.

Sitemap Generator

Free sitemap generator tool. Create XML sitemap for your website easily. Add URLs, set priorities, and generate SEO-friendly sitemap.xml file online.

UUID Batch Generator

Generate up to 10,000 UUIDs in versions 1, 4, 7 or 8. Export as TXT, CSV, JSON or SQL INSERT VALUES. Time-ordered v7 for DB primary keys.

UUID Generator

Generate UUID v1, v4, v5, v7 and Nil GUID with crypto.randomUUID. Bulk up to 100, uppercase, hyphens, braces, RFC 4122 / 9562 compliant.

WiFi QR Generator

Generate WiFi QR codes instantly. Scan to auto-connect — no password typing. Supports WPA/WPA2/WPA3, WEP, open networks, and hidden SSIDs.

Testing & Debugging 7

HTML Previewer

Write HTML, CSS and JavaScript with instant live preview. Split-screen editor, console output and fullscreen mode for web development and prototyping.

WebSocket Tester

Connect to any ws:// or wss:// endpoint, send/receive messages live, see full history with timestamps. For debugging chat, GraphQL subs, MQTT-over-WS.

API Request Tester

Browser-based REST client — GET/POST/PUT/PATCH/DELETE, custom headers, JSON/XML body, response timing. Free Postman-lite for API debugging.

HTTP Header Viewer

HTTP response header inspector — status code, content-type, CSP, HSTS, cache, cookies, CORS. Shows your own request headers too. Browser-only.

C Sandbox

Online C sandbox — compile and run C11 code via GCC 10.2 in your browser. Custom compiler flags, stdin support, 6 starter examples. Zero install.

Python Sandbox

Run Python 3 in your browser via Pyodide (CPython on WebAssembly). Full stdlib, pip via micropip, persistent session, offline after first load. Zero install.

Regex Tester

Free online regex tester tool. Test and debug regular expressions with real-time matching, syntax highlighting, capture groups, and flag support. Perfect for developers working with pattern matching and text processing.

Utilities 18

Google Fonts Pair Finder

Discover perfect Google Fonts pairings for your website. Preview heading and body font combinations with live examples. Get instant CSS code for beautiful typography. Free online font pairing tool for web designers.

URL Slug Generator

Free online URL slug generator. Convert text into clean, SEO-friendly URL slugs. Perfect for creating web-safe URLs, permalinks, and file names. Customize separators, case, and formatting options.

WHOIS Lookup

WHOIS / RDAP domain lookup — registrar, expiry date, nameservers, status flags, DNSSEC. Supports 1500+ TLDs via official IANA bootstrap.

Robots.txt Tester

Free online robots.txt tester and validator. Test if URLs are allowed or blocked by robots.txt rules for different search engine bots. Perfect for SEO and web developers.

User-Agent Parser

Decode any User-Agent string — browser, version, OS, device, engine, bot. Auto-fills your own UA. For analytics, QA, and bot triage.

CSS Specificity

Compute CSS specificity for any selector. Color-coded breakdown, multi-selector comparison, handles :is, :not, :has, :where per the W3C spec.

HTML to JSX

Convert HTML to JSX for React. Renames class→className, for→htmlFor, parses style strings to objects, self-closes void elements, handles SVG attrs.

HTTP Status Codes

Complete HTTP status code reference. Search 60+ codes (100–511) with definitions, RFC links, use cases. Covers 200 OK, 301, 404, 429, 500 + every standard code.

Mermaid Editor

Free Mermaid live editor. Write Mermaid syntax on the left, see flowcharts, sequence diagrams, gantt charts, ER and more rendered live on the right. Export as SVG or PNG.

Subnet Calculator

Free IPv4 subnet calculator. Enter an IP and CIDR or netmask to get network, broadcast, usable host range, total/usable hosts, binary view, and split subnets.

AI Context Bundler

Split long code, docs or transcripts into model-aware numbered chunks for pasting into Claude, GPT, Gemini or Llama. Token estimate, cost preview, overlap.

Cron Expression Parser

Free online Cron Expression Parser and explainer. Parse, validate, and understand cron schedule expressions for Linux, Unix, and Quartz with human-readable descriptions and next run times. Perfect for developers and system administrators.

Diceware passphrase generator

Free Diceware passphrase generator using the EFF long wordlist and WebCrypto. Pick word count, separator, see entropy bits and crack-time estimates.

JSON to TypeScript

Free JSON to TypeScript converter. Paste any JSON, get strict interfaces with nested types, optional fields, and nullable variants. No signup.

JavaScript Obfuscator

Free online JavaScript obfuscator tool. Protect your JavaScript code by obfuscating and encrypting it. Make your JS code unreadable while maintaining functionality.

Markdown cheatsheet

Free searchable Markdown cheatsheet covering CommonMark and GitHub Flavored Markdown: headings, lists, links, code, tables, callouts, math, and more.

OpenAPI Spec Validator

Paste an OpenAPI 3.x JSON or YAML spec, lint it, summarize endpoints, and catch missing 401/403, undeclared params, and other common issues. Free, browser-only.

cURL to Code

Convert any cURL command into JavaScript fetch, axios, Python requests, PHP cURL, Node.js, Go, Ruby, Java, C#, Rust or Swift code instantly. 100% client-side.

File Tools 1

File Compare

Compare two text, code, JSON or CSV files line by line with syntax highlighting. Shows additions, deletions and changes in a unified or side-by-side view.

Fun Tools 5

Fake Android Update

Generate a realistic fake Android system update screen with Pixel, Samsung, Stock and Bootloader themes. Fullscreen prank with progress and ESC exit. Safe.

Fake Virus Scan

Generate a realistic fake antivirus scan with Norton, McAfee, Avast and Generic themes. Rotating file paths, threat counter, alert screen. Safe browser prank.

Fake XP BSOD

Generate the classic Windows XP Blue Screen of Death. Custom STOP code, driver name and memory dump. Fullscreen prank, press any key or ESC to exit. Safe.

Fake iOS Update

Generate a realistic fake iOS update screen with iPhone lockscreen style. Apple logo, progress ring, Update Requested and Verifying themes. Safe ESC-to-exit.

Fake macOS Update

Generate a realistic fake macOS update screen (Sonoma, Ventura, Recovery). Fullscreen prank with Apple logo, progress bar and ESC-to-exit. Safe browser-only.

Hardware Tools 1

Connectivity 1

USB Device Viewer

Inspect USB devices in your browser via WebUSB: view vendor & product IDs, manufacturer, USB version, configurations, interfaces and endpoint details.

Image Tools 2

Barcode Generator

Generate Code128, Code39, EAN-8/13, UPC-A/E, ITF-14, Codabar and MSI barcodes. Adjust width, height, font, margin and download SVG, PNG or PDF — all in browser.

QR code decoder

Free online QR code decoder. Upload a photo or use your camera to read the text or URL inside any QR code. Runs locally in your browser, no upload.

Time Tools 1

ISO Date Converter

Convert ISO 8601 to Unix epoch, RFC 3339, SQL DATETIME, week date and ordinal date with 4 simultaneous timezones, relative time, and Excel/Julian serials.