The study aimed to design a web-based estimating management system that would help the freelance contractor to estimate the overall project costs and applying descriptive analytics; to develop the proposed construction estimating management system for small-medium scale contractor that is accessible anytime and anywhere using open source technologies such as PHP and MySQL; and to evaluate the acceptability of the proposed construction estimating management system by gathering important feedback from users. ISO 25010 standard for software quality was utilized to evaluate the functionality, reliability, performance, usability, maintainability, and security of the project. Based on the responses of freelance contractors it was proven that the system can let the client view and have a copy of the quotation. Applying descriptive analytics for the company’s revenue helps the company to monitor the status of the construction project. The respondents encountered a degree of difficulty on using the traditional method and it indicates that the respondents experienced problems in rough estimating, organizing previous projects, retrieving old records that can be used as a basis for new projects and monitoring the revenue of the company. Important features are considered in the development of the system such as login, logout, viewing of data reports, search projects, project category, company’s revenue, and help assistant. It is important that everyone must engage in upgrading the style of what we know in the past by means of the learning experience and utilizing modern technology is one way to accomplish. Hence, the researcher recommends that the developed Construction Estimating Management System (CEMS) needs to be studied more and enhance more in terms of its function technicalities for there might be more to be considered on it.