---
title: Override a Set-Cookie header with a certain value
description: Get a specific `Set-Cookie` header and update it with a certain value.
image: https://developers.cloudflare.com/core-services-preview.png
---

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# Override a Set-Cookie header with a certain value

Get a specific `Set-Cookie` header and update it with a certain value.

JavaScript

```
export default {  async fetch(request) {    // Receive response from the origin    const response = await fetch(request);
    // Create a new Headers object to modify response headers    const newHeaders = new Headers(response.headers);
    // Get all Set-Cookie headers    const cookieArray = response.headers.getSetCookie();    if (cookieArray.length > 0) {      const updatedCookies = cookieArray.map((cookie) => {        // For example, replace the currency value with GBP        if (cookie.trim().startsWith("currency=")) {          return cookie.replace(/currency=[^;]+/, "currency=GBP");        }        return cookie;      });
      // Delete the existing Set-Cookie headers      newHeaders.delete("Set-Cookie");
      // Add the updated Set-Cookie headers individually      updatedCookies.forEach((cookie) => {        newHeaders.append("Set-Cookie", cookie.trim());      });    }
    // Return the modified response with updated headers    return new Response(response.body, {      status: response.status,      headers: newHeaders,    });  },};
```

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```