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# COOP COEP CORP generator

Builds a compatible COOP, COEP, CORP and CORS header set from a stated goal and four selects, adds Report-Only twins, and calls out conflicts before anything is deployed.

This page assembles header values; it does not know your server's routes or your CDN's behavior, so preflight headers like Access-Control-Allow-Methods stay yours to write. The credentialed CORS block exists because one static Access-Control-Allow-Origin value cannot serve an allowlist: your server has to read the request's Origin and reflect it only when it matches. After deploying an isolation bundle, document.crossOriginIsolated in the console is the real verdict.
Options

## More web & auth tools

- [CSP evaluator & builder](/web/csp)
- [HTTP header parser](/web/headers)
[All web & auth tools](/web)

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Canonical HTML: https://nutter.tools/web/cross-origin-policy-bundle-generator
Markdown version: https://nutter.tools/web/cross-origin-policy-bundle-generator.md
Plain-text version: https://nutter.tools/web/cross-origin-policy-bundle-generator.txt
Agent index: https://nutter.tools/llms.txt