# QScan

> QScan (https://qscan.meklink.com) is a free, open-source post-quantum TLS and security header checker. One scan tests TLS 1.0–1.3, post-quantum ML-KEM key exchange (X25519MLKEM768), the SSL certificate and HTTP security headers, then grades the site A+ to F.

## What QScan checks

- TLS versions: TLS 1.0, 1.1, 1.2 and 1.3. TLS 1.0/1.1 are flagged as insecure (deprecated by RFC 8996).
- Post-quantum key exchange: X25519MLKEM768 and other ML-KEM groups (NIST FIPS 203).
- SSL certificate: issuer, expiry and days remaining, key type and size, trust and hostname match.
- Security headers: Strict-Transport-Security, Content-Security-Policy, X-Frame-Options and X-Content-Type-Options, each rated Protected, Weak or Missing.

## Grading

- A+ needs TLS 1.3, no legacy TLS, a valid certificate, strong HSTS and all four headers. ML-KEM support earns a bonus.
- An untrusted, expired or mismatched certificate is always F. TLS 1.0/1.1 caps the grade at B.

## Usage

- English: https://qscan.meklink.com
- Thai: https://qscan.meklink.com/th
- Link a result: https://qscan.meklink.com/?s=example.com
- Free, nothing stored. Only scan sites you own or are allowed to test.

## Links

- [Source code and documentation](https://github.com/Jakkapan-a/qscan)
- [License: MIT](https://github.com/Jakkapan-a/qscan/blob/main/LICENSE)