COOP / COEP Header Generator

Generate Cross-Origin Opener/Embedder Policy headers for isolation — runs 100% in your browser. No data is uploaded; nothing leaves your device.

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Cross-Origin-Opener-PolicyCross-Origin-Embedder-Policy

Cross-Origin-Opener-Policy: same-origin
Cross-Origin-Embedder-Policy: require-corp

✓ This combination makes the page cross-origin isolated — unlocking SharedArrayBuffer, high-resolution timers and Wasm threads.

COOP isolates your browsing context from cross-origin windows; COEP blocks loading cross-origin resources without explicit opt-in. Together they enable crossOriginIsolated. Runs entirely in your browser.

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Reach for COOP / COEP Header Generator whenever you need to generate Cross-Origin Opener/Embedder Policy headers for isolation. Web developers and security engineers use it to harden a site before launch, fix failing securityheaders.com or Mozilla Observatory scans, and meet client or compliance security requirements.

How to embed COOP / COEP Header Generator on your website

Add this free tool to your own site, blog or intranet — it's 100% free to embed. Paste this snippet where you want the tool to appear; it loads a clean, self-contained version with no ads or navigation.

<iframe src="https://tooljolt.com/embed/coop-coep-generator" title="COOP / COEP Header Generator" width="100%" height="640" style="border:1px solid #e5e7eb;border-radius:12px" loading="lazy"></iframe>

About COOP / COEP Header Generator

COOP / COEP Header Generator is a free online web-security header tool that lets you generate Cross-Origin Opener/Embedder Policy headers for isolation. It runs entirely in your browser — no sign-up, no uploads and nothing ever sent to a server — so it is fast, private and safe to use with sensitive data. Whether you are a developer, security professional, student or just curious, COOP / COEP Header Generator gives you an instant, reliable result with zero setup.

How to use COOP / COEP Header Generator

1Pick the options you want in COOP / COEP Header Generator.
2Copy the generated header (or meta tag).
3Add it to your server, CDN or framework config.
4Re-test with a security-headers scanner to confirm.

Why use COOP / COEP Header Generator?

✓100% free with no sign-up, accounts, watermarks or usage limits
✓Runs entirely in your browser — your input never leaves your device, ideal for confidential security data
✓Hardens your site against XSS, clickjacking and data leaks
✓Improves scores on Mozilla Observatory and securityheaders.com
✓Works on any device with a modern web browser, online or offline

Frequently asked questions

Where do I add the output from COOP / COEP Header Generator?+

Send it as an HTTP response header from your server or CDN (Nginx, Apache, Cloudflare, Vercel, etc.). Many headers can also be set via a meta tag, but the HTTP header is the most reliable.

Will this improve my security score?+

Yes. Correct security headers are checked by tools like Mozilla Observatory and securityheaders.com and defend against XSS, clickjacking and data leaks — a quick win for safety and for the trust signals search engines value.

Is COOP / COEP Header Generator free to use?+

Yes. COOP / COEP Header Generator is 100% free with no sign-up, no account, no usage limits and no watermarks. Use it as often as you like.

Does COOP / COEP Header Generator upload my data to a server?+

No. COOP / COEP Header Generator runs entirely in your browser using JavaScript — nothing you type or upload ever leaves your device. That makes it safe to use with sensitive or confidential security data.