What is HSTS Preloading?
It is a list built into browsers that tells them to use HTTPS for your domain before the first time a user even visits your site.
HSTS Generator — Enforce Permanent HTTPS Security
Generate HTTP Strict Transport Security (HSTS) headers • Configure secure-only connections and preload eligibility
Last updated: May 2026
Generators CSP Policy Builder
default-src
'self'
script-src
'self'
style-src
'self'
'unsafe-inline'
Generated Policy
Copy this policy and add it to your server's Content-Security-Policy header or a <meta> tag to protect your site against XSS and data injection attacks.
Generate perfectly formatted HSTS (HTTP Strict Transport Security) headers. Protect your users from protocol downgrade attacks and get your domain ready for the HSTS Preload list.
• Fact-Checked & Verified•Compliance: 2026 Standards•Last Updated: May 2026
Enterprise-Grade Security Guarantee
WebToolkit Pro is engineered for zero-trust environments. This utility processes your sensitive data entirely within your browser using Web Workers.
Zero server transmission
End-to-end client-side execution
01
How HSTS Policy Generator Works
Users select the security duration and subdomain policies; the tool then generates the header string and server-specific configuration code.
02
Key Features of HSTS Policy Generator
Max-age calculation (up to 2 years)
IncludeSubDomains support
Preload directive integration
Nginx and Apache config snippets
03
Practical Application & Code Integration
Use-Case Context
HTTP Strict Transport Security (HSTS) prevents Man-in-the-Middle (MitM) attacks like SSL Stripping. By generating and deploying an HSTS header, you legally force the browser to establish HTTPS connections for a specified duration (`max-age`), ensuring users cannot be tricked into submitting passwords over an unencrypted HTTP link.
Next.js HSTS Security Header
module.exports = {
async headers() {
return [
{
source: '/(.*)',
headers: [
{ key: 'Strict-Transport-Security', value: 'max-age=63072000; includeSubDomains; preload' }
]
}
]
}
}03
Common Questions About HSTS Policy Generator
Can HSTS break my site?
Yes, if you enable HSTS and then lose your SSL certificate, users will be unable to access your site until the max-age expires. Start with a short duration first.
Looking for more professional developer utilities?
Explore All WebToolkit Pro ToolsEditorial Standards & Processing Transparency
This utility is engineered and maintained under strict editorial and technical standards. All source calculations are audited against official formatting standards and RFC specifications to guarantee mathematical and logic accuracy.
Security Guarantee: To guarantee absolute user privacy, this tool executes 100% client-side inside your web browser. None of your input strings, payloads, keys, or files are ever transmitted to a server or stored externally.
Built by Abu Sufyan • Also explore: Severance Calculator & TradeConvert
Further Reading
Expert guides and technical research related to this tool.
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