SiteQLT program is a system of quality control of web-pages on multiple criteria: - color harmony - readability of text on the background - validation of the HTML/CSS code - speed of page loading - images quality - stability to the screen resolution changing - rankings in search engines As a result of analysis of web-page, the program puts mark from 0 to 10 for each criterion, and the final mark of the totality of all the criteria. In addition, each score is accompanied by details of its calculations and recommendations for its possible improvement. With this program, developers of websites can: - improve the appearance and visualization of web-pages - optimize the speed of web-pages loading - correct errors in the code of web-pages In addition, improving the quality of web-pages promotes the interest of visitors to the website and to raise its rating and promotion to the TOP in search engines.