Free Developer Tool
CSP Decoder
Analyze Content Security Policy headers and understand what each directive does.
default-src
Value - 'self'
Description - Fallback policy for all resource types.
script-src
Value - 'self' 'unsafe-inline'
Description - Controls allowed JavaScript sources.
img-src
Value - 'self' data: https:
Description - Controls allowed image sources.
frame-ancestors
Value - 'none'
Description - Controls which sites may embed this page in frames.
What is CSP Decoder?
CSP headers can become difficult to read. This tool breaks them into human-readable explanations.
How to use
- Paste a CSP header.
- Analyze directives.
- Review explanations.
Features
- Directive parsing
- Readable explanations
- Security auditing
- Developer friendly
- Instant analysis
Example
Input
default-src 'self';
Output
Value - 'self' Description - Fallback policy for all resource types.
FAQ
Does this validate CSP syntax?
Yes. Common CSP syntax errors can be detected.
Can it explain directives?
Yes. Each directive is described in plain language.
Is this useful for audits?
Yes. It helps understand complex CSP configurations.