Simple-Header-Payload

Simple-Header-Payload is a streamlined browser extension designed to add user-defined HTTP request headers, including custom payload strings, exclusively to specified hosts. Ideal for development, debugging, and live environments, this tool lets users precisely control resource access and behavior by modifying headers on targeted web requests.

Available on Google Chrome, Microsoft Edge, and Mozilla Firefox, the extension supports both host names and IPv4/IPv6 addresses. It offers features like adding or appending custom header name-value pairs (including User-Agent), activating or deactivating entries, inline editing of payloads, random payload string generation, and configurable settings visibility. All data resides securely within the browser's internal storage, ensuring privacy and local control.

To use, simply add your target host, define your custom headers and payload, and enable the configuration. The extension then automatically injects the defined headers only when requests match your specified hosts, making it a powerful yet safe tool for web professionals seeking fine-grained request manipulation.