Browser extension to add and modify HTTP request and response headers


ModHeader is fast, efficient, and light-weight. You can quickly enable/disable header modification with just 1-2 clicks.
ModHeader allow you to restrict your modification to just one tab, or only to a certain site.
Consistently rated 4+ stars on Chrome web store and trusted by 300,000+ users.
Automatically backup your changes to the cloud, and restore them automatically. You can also export your profiles and share it with your team.
ModHeader is available on Chrome and Firefox on Windows, MacOS, and Linux.
ModHeader does not inject ad or collect your data. We rely on user contribution to keep it running.


  • Add/modify/remove request and response headers
  • Enable header modification based on URL/resource type
  • Add comments to header
  • Multiple different profiles
  • Sorting headers by name, value, or comments
  • Append value to existing request or response header
  • Export and import header
  • Clone profile
  • Cloud backup
  • Tab locking!



If you like ModHeader, please share it with others, and consider making a donation!
If you use this for your company project, please ask your company to make a monthly donation!

Source codes

Our source code is available on GitHub. Feel free to examine it to make sure it doesn't do anything malicious.