How to use CSP Checker
- Start by adding the text you want to check into CSP Checker.
- Use the Paste a Content-Security-Policy header or policy setting to control the result.
- Watch the output update instantly while you adjust the text.
- Use Copy to keep or reuse the result.
About this tool
There is no server behind CSP Checker. CSP Checker is a free HTTP & Security Header Tools utility that runs in your browser, doing its work on the input you provide without a backend.
It is designed to do one job well and stay out of your way. Your input never leaves the page, and no account or install is required.
Frequently asked questions
How do I use CSP Checker?
CSP Checker lets you check your input right in the browser using the Paste a Content-Security-Policy header or policy control, with the result shown instantly and nothing uploaded.
Is CSP Checker free to use?
Yes — CSP Checker is completely free, with no usage limits.
Does CSP Checker upload my data?
No — CSP Checker processes everything locally in your browser, so nothing you enter is uploaded or stored.
Does CSP Checker work offline?
Once the page has loaded, CSP Checker keeps working with no network connection.