SecurityHeaders.com Alternative

SecurityHeaders.com popularized header grading — but after the Snyk acquisition, its API is being discontinued in April 2026, and it has always been a one-off scanner. HTTPS Checker scans the same headers (HSTS, CSP, X-Frame-Options, X-Content-Type-Options, Referrer-Policy, Permissions-Policy) as part of a full HTTPS report with an A+–F grade — and can keep watching your domain, emailing you when a deploy silently drops a header.

A scanner tells you how things looked when you remembered to check. A monitor tells you when they change. You get both here — free scan below, no signup.

Enter any domain — headers, grade, certificate and redirects in seconds.

User-Agent:

HTTPS Checker vs SecurityHeaders.com

FeatureHTTPS CheckerSecurityHeaders.com
Security headers scan (HSTS, CSP, X-Frame-Options, …)YesYes
Letter grade (A+ to F)YesYes
Continuous monitoring with email alerts on changesYesNo
SSL certificate, expiry & TLS versions in the same reportYesNo
HTTP → HTTPS redirect chainYesNo
HTTP/2 & HTTP/3 (QUIC)YesNo
Certificate Transparency alerts (new cert issued)Paid plansNo
Bulk checkUp to 10 domainsNo
Public JSON APIYesSunset April 2026
PDF / JSON exportYesNo

Alerts on regressions

A framework update removes your CSP, a CDN change drops HSTS — your site keeps working, so nobody notices. Monitoring emails you when any of the six headers appears or disappears, or your grade drops.

More than headers

The same report covers the SSL certificate and expiry, TLS versions, redirect chain, HTTP/2 and HTTP/3, mixed content, CAA and DNSSEC — one grade for your whole HTTPS setup. Paid plans add Certificate Transparency alerts when anyone issues a certificate for your domain.

API that stays

Replacing the SecurityHeaders.com API? Our free public API returns the full report — headers, grade, certificate — as JSON for CI pipelines and dashboards. See the API docs.

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