🔧 DevToolbox — Free Online Developer Tools

20+ free developer tools that run entirely in your browser. No signup. No tracking. No ads.

Tools Included

Tool	Description
JSON Formatter	Format, validate, and minify JSON
Base64 Encoder/Decoder	Encode and decode Base64 strings
URL Encoder/Decoder	Encode and decode URL components
UUID Generator	Generate random UUIDs (v4)
Hash Generator	SHA-1, SHA-256, SHA-384, SHA-512
JWT Decoder	Decode and inspect JSON Web Tokens
Regex Tester	Test patterns with live matching
Color Converter	Convert between HEX, RGB, HSL
Unix Timestamp	Convert timestamps to dates and back
Text Diff	Compare two texts side by side
Lorem Ipsum	Generate placeholder text
Markdown Preview	Live markdown rendering
HTML Entities	Encode/decode HTML entities
CSV ↔ JSON	Convert between CSV and JSON
QR Generator	Generate QR codes from text
Cron Parser	Parse and explain cron expressions
Password Generator	Secure random password generation
Character Counter	Count chars, words, lines, bytes
JS Minifier	Basic JavaScript minification
SQL Formatter	Format SQL queries

Deep-dive cheatsheets for professional developers:

🧠 Prompt Engineering Mega Pack — 50+ battle-tested prompt templates ($4.99)
🔀 Git Power User Cheatsheet — Advanced workflows & recovery ($3.99)
🐳 Docker Compose Cheatsheet — Production-ready patterns ($2.99)
🔍 Regex Mastery Cheatsheet — Patterns & recipes ($3.99)
🐧 Linux CLI Essential Reference — 150+ commands ($4.99)
💻 VS Code Productivity Guide — Shortcuts & extensions ($3.99)
🐚 Shell Scripting Cookbook — 50+ Bash recipes ($4.99) NEW
🔗 API Design Patterns Guide — REST, GraphQL & beyond ($4.99) NEW
🗃️ SQL Query Optimization Guide — PostgreSQL & MySQL ($3.99) NEW
🐍 Python One-Liners Reference — 100+ snippets ($2.99) NEW

MIT — use it however you want.