50+ Free Developer Tools — No Install, No Signup, Runs in Browser

I built a collection of browser-based developer tools that need zero installation. No npm, no Docker, no extensions — just open and use. Here are the ones developers actually keep coming back to: Code Formatting & Conversion JSON Formatter & Validator — paste messy JSON, get it pretty-printed with syntax highlighting and error detection Hex to RGB Converter — convert between hex, RGB, HSL instantly Base64 Encoder/Decoder — encode/decode text and files without leaving your browser URL Encoder/Decoder — handle query strings and encoded URLs Markdown Preview — write and preview markdown in real-time Testing & Debugging Regex Tester — test patterns with live highlighting and match groups DNS Leak Test — check if your VPN is actually protecting you JWT Decoder — decode JWT tokens without pasting them into sketchy online tools Productivity Lorem Ipsum Generator — paragraphs, sentences, or words Cron Expression Builder — build cron schedules visually instead of memorizing the syntax Automatio