🔐 SRI Hash Builder
Professional SRI hash generator that creates secure integrity hashes for web resources. Upload files or paste text to generate SHA-256, SHA-384, and SHA-512 hashes in proper SRI format for CDN security, script validation, and resource integrity verification.
SRI Hash Results:
example-script.js → 3 SRI Hash Formats
SHA-256 • SHA-384 • SHA-512 • Ready for production
📄 File Information
🔐 Generated SRI Hashes
💻 HTML Usage Example
💡 Security Tip: SRI hashes ensure your external resources haven't been tampered with, protecting against CDN compromises and malicious code injection.
🛡️ Security Benefits
Verify external resources
Block modified files
Modern browsers only
How to Use This SRI Hash Builder
The SRI Hash Builder generates cryptographically secure integrity hashes for web resources. Simply paste your content or upload a file, select your preferred hash algorithms (SHA-256, SHA-384, or SHA-512), and get properly formatted SRI hashes ready for production use.
Perfect for:
- CDN resource verification
- External script security
- Stylesheet integrity checking
- File tampering detection
- Compliance with modern web security standards
Generate multiple hash formats simultaneously and get complete HTML usage examples to implement immediately in your projects.
How It Works
Subresource Integrity (SRI) is a security feature that enables browsers to verify that resources they fetch are delivered without unexpected manipulation. Here's how our SRI Hash Builder works:
- Content Processing: Upload a file or paste text content into the generator
- Hash Generation: Creates SHA-256, SHA-384, and/or SHA-512 cryptographic hashes using the browser's native Crypto API
- SRI Formatting: Converts hashes to proper SRI format with algorithm prefix (e.g., "sha256-abc123...")
- HTML Integration: Provides complete HTML tags with integrity attributes ready for copy-paste
- Security Validation: Ensures hashes meet SRI specification standards for maximum browser compatibility
The tool supports all file types and provides instant hash generation without server uploads, keeping your content private and secure.
When You Might Need This
- • Secure CDN JavaScript libraries with integrity verification to prevent malicious code injection
- • Generate SRI hashes for external CSS stylesheets from bootstrap, fontawesome, and other CDN providers
- • Protect WordPress themes and plugins by adding SRI validation to externally loaded resources
- • Create integrity hashes for React, Vue, and Angular production builds served from global CDNs
- • Security auditing: Verify that third-party scripts haven't been tampered with or compromised
- • E-commerce sites protecting payment processing scripts and checkout flows from code injection attacks
- • Educational institutions securing online learning platforms against script modification vulnerabilities
- • Government and healthcare websites meeting security compliance requirements for external resources
- • Web development teams implementing Content Security Policy (CSP) with SRI for enhanced security posture
- • DevOps automation: Generate SRI hashes for deployment pipelines and infrastructure-as-code configurations
Frequently Asked Questions
What is Subresource Integrity (SRI) and why do I need it?
SRI is a web security standard that allows browsers to verify that externally hosted resources (like JavaScript libraries from CDNs) haven't been tampered with. When you include an SRI hash in your HTML, the browser will only execute the resource if its content matches the hash, preventing malicious code injection attacks.
Which hash algorithm should I choose: SHA-256, SHA-384, or SHA-512?
SHA-256 is the most commonly used and recommended for most applications due to its balance of security and performance. SHA-384 offers enhanced security with moderate overhead, while SHA-512 provides maximum security but larger hash sizes. Most developers use SHA-256 unless specific security requirements mandate stronger algorithms.
Do all browsers support SRI hashes?
SRI is supported by all modern browsers including Chrome 45+, Firefox 43+, Safari 13+, and Edge 17+. Older browsers that don't support SRI will simply ignore the integrity attribute and load resources normally, so adding SRI hashes is backward compatible and provides security benefits where supported.
Can I use SRI hashes with files hosted on my own domain?
While SRI works with same-origin resources, it's primarily designed for cross-origin resources like CDN files. For same-origin files, SRI provides limited security benefits since if an attacker can modify your files, they can also modify your HTML. SRI is most valuable for verifying external resources you don't control.
What happens if the SRI hash doesn't match the loaded file?
If the browser detects a mismatch between the resource content and the SRI hash, it will block the resource from loading and display a console error. This protects your site from compromised CDN files or man-in-the-middle attacks, but means you need to update SRI hashes whenever the external resource is updated.