Cook County Launches CookViewer 3.1: Improving Performance and User Experience

The Cook County Bureau of Technology’s Geographic Information Systems (GIS) division is proud to announce the release of CookViewer 3.1, a significant update to Cook County’s flagship property information platform. Originally launched in 2010, this latest version introduces an array of enhancements to performance, compatibility and the user experience across both desktop and mobile devices. 

CookViewer 3.1 is powered by an upgraded mapping engine built on the ArcGIS Maps Software Development Kit for JavaScript, ensuring faster load times, improved compatibility and more seamless interactivity. The app now uses the Calcite Design System 3.0, offering users a more modern and intuitive interface throughout the site. 

“As technology evolves, so must our tools,” said Cook County President Toni Preckwinkle. “CookViewer 3.1 reflects our commitment to keeping public data accessible, navigable and useful to everyone in the county.” 

Among the most visible updates is a new Help dialog and guided tour for first-time users, helping residents better understand the range of tools CookViewer offers. These improvements are part of a broader focus on user experience and education, making it easier than ever to navigate the platform. 

Parcel symbology has also been enhanced, increasing contrast between parcel boundaries and aerial imagery to improve readability. A redesigned Measure tool and streamlined PDF property reports allow for more accurate assessments and convenient printing of detailed property information. 

Additional usability enhancements include standardized panel controls, improved mobile layouts, and new visual cues to support the printing and parcel selection processes. Several bugs have also been resolved to improve stability and eliminate workflow disruptions, particularly in the Comparable Search and Select Multiple Parcels tools. CookViewer is available in both English and Spanish. 

Since its launch in 2010, CookViewer has grown into a trusted tool for residents, businesses, and government agencies alike. With the release of Version 3.1, Cook County continues to prioritize transparency, innovation and equity in delivering geographic information to the public. 

To explore the updated application, visit maps.cookcountyil.gov/cookviewer