A DAST and a config scanner solve different problems
Probely is a paid SaaS dynamic application security testing (DAST) tool aimed at developers and security teams. It crawls your running web application and APIs, launches OWASP-style attack payloads to find vulnerabilities like injection, broken authentication, and cross site scripting, and folds the results into your CI/CD pipeline with compliance reports. It is a subscription product built for deep, active application testing.
That kind of scan takes time to configure and run, and it tends to summarize the configuration layer rather than dig into it. A site can pass an application scan while still missing critical security headers like Content Security Policy and HSTS, serving cookies without Secure or HttpOnly flags, lacking DNS email authentication records, or running without a Permissions-Policy. SiteSecurityScore is purpose built for exactly that layer. It grades your whole configuration surface in seconds, turns every finding into a copy-paste fix, and locks the result in place with free daily monitoring, all with no setup and no sales calls. It is everything you need for the configuration layer in one scan, the essential first move while a DAST handles the deeper application testing.
Probely vs SiteSecurityScore: side by side feature comparison
Configuration Layer
| Feature | SiteSecurityScore | Probely |
|---|---|---|
| HTTP security headers (CSP, HSTS, X-Frame-Options) | Partial | |
| Deep CSP directive-by-directive analysis | ||
| Permissions-Policy, COOP, COEP, CORP checks | ||
| TLS/SSL config and certificate check | Partial | |
| DNS records (SPF, DKIM, DMARC, CAA) | ||
| Cookie security attributes | Partial | |
| CORS, security.txt, mixed content checks | Partial |
Workflow & Output
| Feature | SiteSecurityScore | Probely |
|---|---|---|
| Letter grade scoring | ||
| Copy-paste fix generators | ||
| PDF report generation | ||
| REST API for automation | ||
| CI/CD pipeline integration | via API | |
| MCP connector (Claude Code, ChatGPT Codex) | ||
| Browser extension (authenticated pages) |
Access & Monitoring
| Feature | SiteSecurityScore | Probely |
|---|---|---|
| Free scans, no account for basics | ||
| Instant first-pass results | Partial | |
| Daily monitoring with email alerts | ||
| CSP violation and NEL reporting | ||
| Free header generator tools | ||
| Learning center with guides |
Application Testing
| Feature | SiteSecurityScore | Probely |
|---|---|---|
| Active DAST vulnerability scanning | ||
| OWASP Top 10 web app testing | ||
| API vulnerability scanning | ||
| Authenticated crawl and attack | ||
| Compliance reports (PCI, SOC 2, ISO) |
What Probely covers vs the config layer SiteSecurityScore lives in
Probely focuses on runtime application vulnerabilities. SiteSecurityScore owns the configuration details that decide how safely your site behaves in the browser, and it grades every one of them in seconds. Here is where SiteSecurityScore goes deep.
Security headers analysis
CSP, HSTS, X-Frame-Options, X-Content-Type-Options, Referrer-Policy, Permissions-Policy, COOP, COEP, and CORP. These headers stop XSS, clickjacking, and data leakage, and a DAST often just notes their presence rather than grading them.
Deep CSP analysis
A directive-by-directive breakdown of your Content Security Policy. It flags unsafe-inline, overly broad wildcards, and missing directives, then hands you a corrected policy to copy.
DNS security records
SPF, DKIM, DMARC, and CAA record analysis. Close email authentication gaps before attackers use them for phishing and spoofing.
Cookie security audit
HttpOnly, Secure, SameSite, Path, Domain, and prefix checks for every cookie, so you can spot session hijacking and CSRF risks at a glance.
CORS and mixed content
Reviews Access-Control-Allow-Origin and credentials settings for overly permissive cross-origin rules, and flags mixed content and information disclosure.
security.txt validation
Verifies your security.txt file so researchers can reach you through the proper disclosure channel.
Free continuous monitoring with email alerts
A heavy DAST scan is something you schedule, not something you watch every day. Between scans, a header can be removed in a deploy or a certificate can drift toward expiry without anyone noticing. SiteSecurityScore guards the config layer for you in between, for free.
SiteSecurityScore runs free daily automated scans that check your HTTP security headers, Content Security Policy, TLS configuration, DNS records, and cookie security in a single pass. When anything changes, you get an email alert right away. It also supports CSP violation and Network Error Logging reporting so you can watch how your policies behave in production. No manual re-testing required.
Automated daily scans
Every monitored site is scanned once per day covering headers, CSP, TLS, DNS, and cookies.
Email alerts on changes
Get notified when your security posture changes, a certificate nears expiration, or a header is removed.
Free generator tools that fix the findings
Knowing which headers are missing is only half the job. You also need correct values. SiteSecurityScore includes free generator tools that produce copy-paste configurations for your web server, so every finding turns into a shipped fix in minutes.
Scan authenticated pages and fit your dev workflow
Chrome Extension, REST API, and MCP connector
Server-side scanners can only reach publicly accessible URLs. The SiteSecurityScore browser extension captures real response headers from your authenticated sessions, so you can grade admin panels, dashboards, and staging environments with one click. The REST API and the MCP connector for Claude Code and ChatGPT Codex drop config checks straight into your pipeline or your editor, so security grading lives right where you already work.
Run a free website security scan
Enter any URL and get an instant audit of your HTTP headers, CSP, HSTS, TLS certificates, DNS records, and cookie security. No account required.
Start scanningFrequently asked questions
Is SiteSecurityScore a replacement for Probely?
The two tools cover different layers. Probely is a paid SaaS dynamic application security testing (DAST) tool that probes web apps and APIs for runtime vulnerabilities like injection and broken authentication. SiteSecurityScore is purpose built for the configuration layer that attackers probe first, covering HTTP security headers, deep Content Security Policy analysis, TLS, DNS records, CORS, security.txt, and cookie security. It grades your site in seconds, hands you copy-paste fixes, and watches the config layer continuously for free. It is the essential layer you should not skip, and it pairs perfectly alongside a DAST like Probely for deep application testing.
What does SiteSecurityScore check that a DAST like Probely treats as secondary?
SiteSecurityScore goes deep on the configuration layer that DAST scanners often summarize. It runs a directive-by-directive Content Security Policy analysis, checks HSTS, X-Frame-Options, X-Content-Type-Options, Referrer-Policy, Permissions-Policy, COOP, COEP, and CORP, audits cookie flags (HttpOnly, Secure, SameSite), verifies DNS records (SPF, DKIM, DMARC, CAA), reviews CORS, validates security.txt, and flags mixed content and information disclosure. It turns each finding into a copy-paste fix and a clear letter grade in seconds.
Does SiteSecurityScore do dynamic application vulnerability testing like Probely?
No, and that is the key difference. Probely actively crawls and attacks your running application and APIs to find OWASP-style vulnerabilities such as SQL injection, XSS, and broken authentication, with CI/CD integration and compliance reports. SiteSecurityScore inspects how your site is configured at the header, TLS, DNS, and cookie level. That makes it instant and safe to run on any URL with no account, so you grade and fix the configuration layer attackers probe first before you ever schedule a heavier scan.
Can I monitor my security headers and TLS automatically with SiteSecurityScore?
Yes, and the monitoring is free. SiteSecurityScore runs automated daily scans that check your HTTP security headers, Content Security Policy, TLS configuration, DNS records, and cookies in one pass. You get email alerts the moment something changes, like an expiring certificate or a removed header. It also supports CSP violation and Network Error Logging (NEL) reporting so you can watch your policies in production with zero manual re-testing.
Is SiteSecurityScore free to use as a Probely alternative?
Yes. Probely is a paid subscription DAST aimed at development and security teams. SiteSecurityScore gives you free website security scans covering HTTP security headers, TLS certificates, DNS records, Content Security Policy, and cookie security, with no account and no setup required. You also get free continuous daily monitoring, free header generator tools, a Chrome extension, a REST API, and an MCP connector for Claude Code and ChatGPT Codex, so the fastest path to a graded and fixed posture costs nothing to start.
Can SiteSecurityScore scan pages behind a login?
Yes. SiteSecurityScore ships a Chrome browser extension that captures real HTTP response headers from your authenticated sessions, so you can grade admin panels, dashboards, and staging environments in one click. It also exposes a REST API and an MCP connector for Claude Code and ChatGPT Codex, so security checks drop straight into your existing developer workflow with no extra tooling.