Free Tools
Security tools built for builders.
Practical, browser-based tools for developers, students, and security learners. No sign-up, no tracking, everything runs locally on your device.
JWT Decoder & Inspector
Decode any JSON Web Token in your browser and check it for common security issues: alg: none, missing expiry, long-lived tokens, and sensitive data in the payload.
Secret & Credential Scanner
Paste code or config files to detect exposed secrets: AWS keys, GitHub tokens, Stripe keys, database URLs, hardcoded passwords and more. 19+ patterns, 100% client-side.
Spot the Vulnerability Quiz
Look at real code snippets and identify the vulnerability: SQL injection, XSS, SSRF, IDOR, path traversal, and more. Instant feedback with explanations.
Tools FAQ
Yes. Every tool on this page is free, with no sign-up and no usage limits.
No. Every tool runs entirely in your browser using client-side JavaScript. Tokens, code snippets, and other input you paste in are never transmitted to RestingOwl or any third party.
Developers who want to check a JWT before shipping it, students learning offensive and defensive security, and anyone preparing for CTFs or security certifications.