# Sentryx Monitor

> Sentryx Monitor is a read-only external attack surface monitoring and continuous website security monitoring platform for public customer-facing systems.

## Product

- [External Attack Surface Monitoring](https://sentryxmonitor.com/services/external-attack-surface-monitoring/)
- [Free Website Security Check](https://sentryxmonitor.com/report/)
- [Website Security Check Service](https://sentryxmonitor.com/services/website-security-check/)
- [SSL Certificate Monitoring](https://sentryxmonitor.com/services/ssl-certificate-monitoring/)
- [Website Uptime Monitoring](https://sentryxmonitor.com/services/uptime-monitoring/)

## Knowledge pillars

- [External Attack Surface Management Guide](https://sentryxmonitor.com/learn/external-attack-surface-management/)
- [Networking for Security and Monitoring](https://sentryxmonitor.com/learn/networking/)
- [DNS Security and Monitoring](https://sentryxmonitor.com/learn/dns/)
- [TLS and SSL Certificate Security](https://sentryxmonitor.com/learn/tls/)
- [Cybersecurity Glossary](https://sentryxmonitor.com/glossary/)

## Free tools

- [Free SSL Certificate Checker](https://sentryxmonitor.com/tools/ssl-checker/)
- [Free DNS Checker](https://sentryxmonitor.com/tools/dns-checker/)
- [Free DMARC Checker](https://sentryxmonitor.com/tools/dmarc-checker/)
- [Free Security Header Checker](https://sentryxmonitor.com/tools/security-header-checker/)
- [Free TLS Checker](https://sentryxmonitor.com/tools/tls-checker/)
- [Free Domain Security Checker](https://sentryxmonitor.com/tools/domain-security-checker/)

## Research

- [Sentryx Research](https://sentryxmonitor.com/research/)
- [Outside-In Research Methodology](https://sentryxmonitor.com/research/methodology/)

## Scan method and limits

- Public scans use unauthenticated, outside-in observations.
- They do not log in, exploit systems, access private data, crawl authenticated routes, or fuzz inputs.
- A public scan is not a penetration test, certification, or guarantee that a system has no vulnerabilities.
- Research figures are not published until privacy-qualified aggregate data and disclosure review are complete.

## Identity

- Product: Sentryx Monitor
- Technical author: Sentryx Security Engineering
- Canonical site: https://sentryxmonitor.com/
- Last reviewed: 2026-08-08