CORS Unblock

No more CORS error by appending 'Access-Control-Allow-Origin: *' header to local and remote web requests when enabled

As of May 2026, CORS Unblock has 200,000 users and a 4.08/5 rating from 175 reviews in the Developer Tools category.

Usersno change0%
200.0K
200,000
Ratingno change0%
4.08
175 reviews
Reviewsno change0%
175
Version
0.5.2
Manifest V3

History

2 snapshots

Tracking since Apr 20, 2026.

202.3K200.0K197.7KApr 20, 2026May 30, 2026
View as table
DateUsersRatingReviewsVersion
Apr 20, 2026200.0K4.081750.5.2
May 5, 2026200.0K4.091760.5.2
Now200.0K4.081750.5.2

Permissions & access

Permissions
storagedeclarativeNetRequestdebugger
Host access
<all_urls>

Screenshots

CORS Unblock screenshot 1CORS Unblock screenshot 2CORS Unblock screenshot 3

About

This extension bypasses the "XMLHttpRequest" and "fetch" rejections by altering the "Access-Control-Allow-Origin" and "Access-Control-Allow-Methods" headers for every request that the browser receives. You can activate the extension by pressing the action button. Also, use the right-click context menu over the action button to modify which headers the extension manipulates. You can also ask the extension not to overwrite these headers when the server returns values for them.

The default values for the headers:

Access-Control-Allow-Origin: request initiator or empty
Access-Control-Allow-Methods": GET, PUT, POST, DELETE, HEAD, OPTIONS, PATCH, PROPFIND, PROPPATCH, MKCOL, COPY, MOVE, LOCK
Access-Control-Allow-Methods: request initiator or empty 
Access-Control-Allow-Credentials: true
Access-Control-Expose-Headers: request initiator or *

Additional Features:
1. It can remove the following CSP-related headers: 
"Content-Security-Policy", "Content-Security-Policy-Report-Only", "X-WebKit-CSP" and "X-Content-Security-Policy".

2. It can overwrite the returned 4xx status code from the server. Use this feature when a server does not support a method, but you want to pretend it does. 

3. It can append necessary headers to pretend websites (local or remote hosts) support SharedArrayBuffer class. 

4. It can permit cross-origin frame embedding (by removing the "X-Frame-Options" header) to simplify remote page embedding during local development.

5. It can include or exclude the "referer" and "origin" headers when a server is sensitive to them to work appropriately.

6. The extension optionally uses the "chrome.debugger" to overwrite 4xx status codes (in case a server does not support a method, you can use this feature to pretend the server accepts a response or supports an unsupported method).

7. The extension also optionally fixes CORS policies of redirected URLs.

--
It is important to note that this extension fixes preflight requests to permit access to any custom header (when enabled). 

Links:
1. For reporting bugs, please use the link https://github.com/balvin-perrie/Access-Control-Allow-Origin---Unblock.

2. To have better control over CSP (content-security-policy), try my https://chrome.google.com/webstore/detail/csp-unblock/lkbelpgpclajeekijigjffllhigbhobd.

Technical

Version
0.5.2
Manifest
V3
Size
198KiB
Min Chrome
88
Languages
1
Featured
No

Metadata

ID
lfhmikememgdcahcdlaciloancbhjino
Developer ID
u892a251722229e96a42d8c5d4004044c
Developer Email
[email protected]
Created
Jan 25, 2019
Last Updated (Store)
Jun 3, 2025
Last Scraped
May 30, 2026
Website

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Data sourced from the Chrome Web Store · last verified May 30, 2026.