Free Tools
Security & Developer Tools
Free, browser-based tools for developers and security professionals. No sign-up, no data collection — everything runs locally in your browser.
15
Tools
100%
Client-side
0
Sign-up required
All
Security
Network
Developer
Content
Network
Website Latency Tester
Fire parallel GET requests to multiple endpoints and visualise latency in real-time with live charts.
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Developer
SEO & GEO Checker
Analyse a website for traditional SEO signals and Generative Engine Optimisation (GEO/AI) readiness.
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Security
JWT Analyzer
Decode and analyse JSON Web Tokens — inspect header, payload, claims, expiry and security issues.
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Developer
JSON Viewer
Paste, format, validate and explore JSON with collapsible tree view, search and sort capabilities.
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Security
CORS Policy Tester
Test CORS configuration — fire preflight and simple requests, inspect cross-origin headers and policies.
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Security
CSP Header Generator
Build a Content Security Policy interactively — configure directives, get Nginx/Apache config snippets.
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Security
Password Entropy Checker & Generator
Analyse password strength, estimate crack times, and generate cryptographically secure passwords and passphrases.
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Security
HTTP Security Headers Checker
Audit a website's HTTP response headers — detect missing or misconfigured security protections with a grade.
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Developer
Regex Tester
Test regular expressions in real-time — highlight matches, inspect capture groups, replace and validate patterns.
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Developer
Base64 / URL / Hash Encoder
Encode and decode Base64, URL encoding, HTML entities, compute SHA hashes and convert hex/binary.
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Content
Markdown to HTML Converter
Write Markdown with a live HTML preview — format, export, download as .html or .md with toolbar shortcuts.
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Security
Threat Model Generator
Build a STRIDE-based threat model — define assets, actors and threats, export a structured security report.
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Security
Secure Cookie Analyzer
Paste Set-Cookie headers and get a full security analysis of HttpOnly, Secure, SameSite and other attributes.
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Security
Dockerfile Risk Scanner
Scan Dockerfiles for security misconfigurations, hardcoded secrets, root usage and best-practice violations.
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Network
IPv4 Tools
Subnet calculator, IP analyser, CIDR host list, integer/hex/binary conversion, subnet splitter and private range reference.
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