Free security tools

Fast, accurate tools for the day-to-day work of testing and triaging vulnerabilities. No sign-up, no adverts, no tracking — each one runs entirely in your browser, so nothing you paste or type ever leaves your machine.

Vulnerability scoring

CVSS 3.1 Calculator

Score a vulnerability against the FIRST CVSS v3.1 specification. Set base, temporal, and environmental metrics; get the score, severity, and a shareable vector string.

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How our tools work

Private by design. Everything runs client-side in your browser. We do not receive, log, or store anything you enter.
Standards-accurate. Where a tool implements a published standard, it follows the specification exactly and is tested against known reference values.
No account, no cost. Free to use and free to link to or share via the URL.

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