Security Headers Checker

The Security Headers Checker is a free Linkslo SEO utility for security & https work. Inspect common security-related response headers such as HSTS, CSP and X-Content-Type-Options.

Focused checks help teams verify one signal clearly before broader changes. Template-level mistakes often repeat across many URLs, so catching them early protects both users and crawl efficiency.

1. 1Enter the page URL you want to inspect with the Security Headers Checker.
2. 2Run the check and review pass, warning and error results.
3. 3Open technical details for the exact signals detected.
4. 4Fix high-impact issues first, especially those that affect users or crawl clarity.
5. 5Re-test the URL after deployment to confirm the change is live.

• Treat results as evidence for a specific question, not a final ranking score.
• Context matters: a warning can be acceptable on some templates and urgent on others.
• Compare important commercial or informational URLs against known good examples on your site.
• Combine this check with manual review when the page serves a unique business purpose.

• Issues are ignored until rankings move, then fixed incompletely under pressure.
• Template mistakes get copied across many URLs.
• Scores are optimized while user clarity is ignored.
• Changes are deployed without a re-test of the live URL.

• Prioritize issues that affect users, crawl paths or clear content understanding.
• Fix shared templates once so corrections apply broadly.
• Document the preferred pattern for writers and developers.
• Re-run the tool after release and keep a short before/after note for stakeholders.

• Use the Security Headers Checker during content production and technical QA, not only after problems appear.
• Keep standards written and shared so freelancers and agencies follow the same rules.
• Pair automated checks with human review of the rendered page.
• Track recurring issues so the root cause can be fixed in the CMS or design system.

Professionals use the Security Headers Checker as a scoped diagnostic. Start with pages that drive revenue or rankings, interpret warnings in template context, and avoid treating any single metric as a ranking guarantee. When the same issue repeats, fix the system that creates it—content guidelines, CMS defaults or shared components—rather than only patching one URL.

The Security Headers Checker inspects the signals available from the input you provide. It cannot see Google's private index state, every JavaScript-only experience beyond the fetched response, or every business constraint unique to your site.