This paper discusses the development of a web-based application named Synchronizer to enhance the capability of the NEESCentral Web Portal. The NEESCentral Web Portal is a cyberinfrastructure tool available to all NEES participants and is designed to provide a simple way for researchers to share and archive their project data with NEES Repository. Synchronizer has been developed to assist multi-member projects in organizing and sharing local data with NEES Data Repository frequently. Synchronizer allows project members to connect to NEES Data Repository to download and upload data in bulk where the application automatically checks for updated files with options to replace, rename, or to keep them all. The application also allows the project administrator to put different restrictions on each project member in accessing the files and sub-directories. Synchronizer uses Mozilla Fire Fox for obtaining “GAsession ID” cookie and Internet Explorer for executing the application. The code has been developed with HTML embedded scripting language PHP, MySql open-source database, Microsoft Window Software Development Kit (Microsoft Platform SDK), GNU Wget, and Adobe Macromedia Dreamweaver web design and development tool. Users from the Pathways project have given Synchronizer very good comments.