DevKit Sidebar

Local-only developer toolkit sidebar with JSON, Config, Cron, URL, Time, Compare, JWT, Hash, Regex, SQL, and Shelf tools.

DevKit Sidebar is a local-first developer toolkit built into Chrome's native Side Panel. It stays open while you work — no popups, no tab-switching, no leaving the page you're debugging. Every tool runs entirely inside the extension. No accounts. No telemetry. No third-party anything. TOOLS { } JSON Formatter & Validator Format, minify, validate, and syntax-highlight JSON. Instant feedback on structure and errors. ⚙ Config Formatter Paste messy .env or key/value config text and get it back clean, readable, and ready to edit. 🕒 Cron Helper Build and verify cron expressions without leaving your browser. Know exactly when your job runs. 🔗 URL Encoder / Decoder Encode or decode URLs in one click. Handles %20, +, and full-encode variants. ⏱ Timestamp Converter Convert between UNIX timestamps and human-readable date/time — in both directions, instantly. ⇄ Text Compare Paste two blocks of text and see exactly what changed. Great for config diffs and API responses. 🔑 JWT Decoder Split any JWT into its header, payload, and signature. Expiration status shown at a glance. # Hash Generator Generate MD5, SHA-1, SHA-256, SHA-384, and SHA-512 hashes simultaneously. One-click copy per hash. . Regex Tester* Write a pattern, add flags, paste a test string — matches and capture groups highlighted live. ⛃ SQL Formatter Format raw or minified SQL into clean, clause-by-clause structure. Choose uppercase or lowercase keywords. 🗂 Shelf A local scratchpad for snippets, notes, drafts, and pasted assets. Persists between sessions. PRIVACY DevKit Sidebar keeps your data on your device — always. No analytics or telemetry No remote data collection No third-party trackers The only storage used: Theme and zoom preferences → browser localStorage Shelf items and assets → browser IndexedDB Nothing is sent anywhere. Everything stays local. PERMISSIONS DevKit Sidebar requests the minimum necessary: sidePanel — run in Chrome's native Side Panel clipboardRead — for paste actions you trigger clipboardWrite — for copy actions you trigger No host permissions. No access to page content. No network calls.