Install Requestly from the Chrome Web Store. Open the dashboard to create a rule (e.g., "Modify Headers" or "Cancel Request"). Define your criteria, and the extension will automatically tamper with the data in the background. 2. ModHeader

: Allows you to modify API responses or web content locally and have those changes persist through page refreshes. Open DevTools ( F12 ) → Network tab. Right-click a request and select Override content . Select a local folder to store the modified data. Edit the file in the Sources panel and save.

While dedicated proxy tools like OWASP ZAP or Burp Suite are industry standards, Google Chrome provides powerful built-in features and extensions that allow you to tamper with data directly inside the browser. What is Data Tampering in a Browser?