HSTS Preload Checker & Header Generator
Check HSTS preload eligibility and generate Strict-Transport-Security headers with proper directives.
Tool Upgrade Coming Soon
This tool is currently a preview template. We are actively upgrading it to 100% blueprint compliance with 10 extra features. Like all UnQTools features, the upgraded version will run 100% locally in your browser with zero network requests.
About HSTS Preload Checker & Header Generator
Check HSTS preload eligibility and generate Strict-Transport-Security headers with proper directives. Everything runs locally in your browser — your data never leaves your device.
How to use
- Enter your input in the tool above.
- Adjust any options to your preference.
- Use the Copy or Download buttons to save the result.
- Everything happens locally — your data never leaves your browser.
FAQ
What does this tool do?
Check HSTS preload eligibility and generate Strict-Transport-Security headers with proper directives.
Is my data sent to a server?
No. This tool runs 100% in your browser. Nothing is uploaded, tracked, or stored remotely.
What extra features does this tool have?
Extras: (1) (1) HSTS header generator, (2) (2) max-age directive, (3) (3) includeSubDomains, (4) (4) preload directive, (5) (5) Preload eligibility checklist, (6) (6) HSTS preload submission URL, (7) (7) Common misconfigurations, (8) (8) Header validation, (9) (9) Copy header, (10) (10) Nginx/Apache config, (11) (11) Export config, (12) (12) PWA offline
Does this work offline?
Yes — install as a PWA and use it without network.
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