HTTP Strict-Transport-Security Header Regex for Go

What this pattern does

This page provides a well-structured, multi-part regular expression for matching http strict-transport-security header, ported and verified for Go. In security-sensitive code, using an unverified regex can open the door to both false positives and denial-of-service attacks. The snippet below is ready to drop into your Go project — whether you're validating in a Gin handler, a gRPC service, or a command-line tool.

Go Implementation

// HTTP Strict-Transport-Security Header
// ReDoS-safe | RegexVault — Security > Security Headers

package validation

import "regexp"

var httpStricttransportsecurityHeaderRe = regexp.MustCompile(`^max-age=([0-9]+)(?:;\s*includeSubDomains)?(?:;\s*preload)?$`)

func ValidateHttpStricttransportsecurityHeader(s string) bool {
    return httpStricttransportsecurityHeaderRe.MatchString(s)
}

// Example
// fmt.Println(ValidateHttpStricttransportsecurityHeader("max-age=31536000")) // true

Test Cases

When to use this pattern

This pattern is drawn from the Security > Security Headers category and carries a ReDoS-safe certification. That matters for Go developers because Go's RE2 engine is inherently safe from catastrophic backtracking, but this pattern has been additionally verified for correctness. RegexVault audits patterns against known backtracking attack vectors, ensuring you have the necessary context before using this regex in a high-stakes production environment.

Common Pitfalls

Technical Notes

HSTS tells browsers to only connect via HTTPS. min max-age for HSTS preloading: 31536000 (1 year). max-age=0 disables HSTS. includeSubDomains extends to all subdomains. preload submits to Chrome/Firefox preload lists — be careful, it is very hard to undo. Capture group 1: max-age value in seconds.