Fiddler - Fiddler is a debugging program for websites.
HostedScan.com - Online vulnerability scanner for servers, networks, and web applications.
Proxyman.io - Proxyman is a high-performance macOS app, which enables developers to view HTTP/HTTPS requests from apps and domains.
HackerTarget.com - Security Vulnerability Scanning based on Open Source Tools.
HTTP Toolkit - Beautiful, cross-platform & open-source tools to debug, test & build with HTTP(S). One-click setup for browsers, servers, Android, CLI tools, scripts and more.
Acunetix - Audit your website security and web applications for SQL injection, Cross site scripting and other...