Best extension to modify request headers response headers authorization header set-cookie header

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As featured on

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Why ModHeader

ModHeader is fast, secured, and light-weight. You can quickly enable/disable header modification with just 1-2 clicks.
ModHeader allow you to set up URL filter, tab filter, window filter, resource type filter, etc.
Consistently rated 4+ stars on Chrome Web Store and used by 600,000+ users.
Easily export and share your profiles with others. Automatically backup your changes to the cloud.
ModHeader is available on Chrome, Firefox, and Edge on Windows, MacOS, and Linux.
ModHeader does not inject ad or sell your data.

Modify headers with ease

You can quickly modify request header, response header, cookie request header, set-cookie response header, etc.

Modify request and response headers

Toggle changes with a single click

Quickly toggle the modification on and off to test different behaviors.

Toggle modifications

Smart filters

Want to limit your changes to some websites? With URL filter, tab filter, resource type filter, etc., you can avoid leaking your changes to other websites unintentionally.

URL filters

Modify individual cookies

Modify individual cookies in Set-Cookie response header, rewrite their values, and configure their attributes.

Configure cookies

Configure CSP like a pro

Easily author complex CSP, test them, and copy them to your production configuration.

Configure CSP

Sharing profiles

Want to share your ModHeader profile with your teammate? You can export your profile with the click of a button.

Share profiles


You can setup different header modifications and filters on separate profiles, and quickly switch between them.

Switch profiles

...and more:

  • Redirect URL with another
  • Add comments to header
  • One-click "undo" if you made a mistake
  • Customize autocomplete names and values
  • Dark mode support
  • Sorting headers and name, value, or comments
  • Append value to existing request or response header
  • Customizable profile badge
  • Clone profile
  • Cloud backup
  • Time filter
  • WebDriver support
  • Enterprise policy support