According to WikiPedia

Cross-site scripting is a type of computer security vulnerability typically found in web applications. XSS enables attackers to inject client-side scripts into web pages viewed by other users. A cross-site scripting vulnerability may be used by attackers to bypass access controls such as the same-origin policy.

xssizer helps penetration tester, bug hunters and other security professionals to easily detect such vulnerabilities and produces a ready-to-use PoC exploit for demostration.

Installation

git clone https://github.com/noLogicXD/xssizer.git
 cp xssizer -r /var/www/html/xssizer
 service apache2 start

Then open localhost/xssizer/pro.php in your browser.

User interface
xssizer has a user friendly and straight forward interface


Testimonies
xssizer's private beta version recieved tremendous amount of appreciation from the beta testers. Here are some of the best compilments

Mahmoud Osama "I have to say that Brute Logic's KNOXSS is the best XSS tool I have ever seen! I have just got rewarded with bounty on YesWeHack for DOM XSS."

Hussain Adnan "You buy KNOXSS for ~$100 and by it [you] win $5000!"

Emad Shanab "I would like to thank KNOXSS for bypassing Akamai WAF and getting the magic alert box in famous credit card company."

Words from Author
Thank you for using xssizer. Please follow me on twitter @SecurityJoker.