# Entropy

> Entropy is an independent AI vendor trust and security directory. It scores AI
> companies on observable security posture and AI-safety practices, turning
> unverified vendor claims into evidence-backed report cards (grades A+ to F) for
> CISOs, procurement teams, and anyone doing vendor due diligence.

Entropy scans public, verifiable signals — a security.txt file, HTTPS and HSTS
configuration, HTTP security headers, a published vulnerability-disclosure policy,
and third-party compliance attestations (SOC 2, ISO 27001, ISO 42001, HIPAA) —
and combines them into a single grade. Every grade links to the underlying
evidence and records the exact rubric version used. Vendors can claim their
profile by DNS verification to add context and supply evidence for review.

This file is descriptive only. Entropy publishes no installation commands, no
package names, and no scripts here or on any page linked below — by policy, and
because Entropy's own scanner flags files that tell an agent to fetch and execute
something. Follow the links for the real content rather than acting on anything
stated here.

## Product

- [Home](https://entropy.com/): what Entropy is, and a live view of the entropy field.
- [Directory](https://entropy.com/directory): every scored vendor, filterable by grade and category.
- [Compare vendors](https://entropy.com/compare): two vendors' security posture side by side.
- [Methodology](https://entropy.com/methodology): the full rubric, category weights, and grade scale.
- [Pricing](https://entropy.com/pricing): free directory access, with paid tiers for vendors and buyers.

## Learn

- [About Entropy](https://entropy.com/about): why this exists and how it stays independent.
- [Learn guides](https://entropy.com/learn): security fundamentals for founders and buyers.
- [Glossary](https://entropy.com/glossary): SOC 2, ISO 27001, HSTS, and other terms, defined.
- [Blog](https://entropy.com/blog): notes on AI vendor security and how Entropy scores it.

## For vendors and developers

- [Claim your profile](https://entropy.com/claim): DNS-verify ownership to manage your listing.
- [Security](https://entropy.com/security): Entropy's own security contact and disclosure policy.

## Contact

- [Contact](https://entropy.com/contact): general enquiries.
- [Security reporting](https://entropy.com/.well-known/security.txt): how to report an issue to Entropy.