While sea level rise is a world-wide phenomenon, mitigating its impacts is a local decision-making challenge that is going to require site-specific remedies. Faced with a variety of conflicting mandates and uncertainty as to appropriate responses, local land use planners and managers need place-based decision support tools. With the increasing availability of high-resolution digital elevation models and the advancing speed and sophistication of web-based mapping, a number of web geographic information systems (GIS) tools have been developed to map and visualize what areas of a coastal landscape will potentially be flooded under different scenarios of sea level rise. This paper presents a case study of one such WebGIS application, NJFloodMapper (www.NJFloodMapper.org), with a focus on the user-centered design process employed to help our target audience of coastal decision-makers in the state of New Jersey, USA, access and understand relevant geographic information concerning sea level rise and exposure to coastal inundation, as well as assess the vulnerability of key infrastructure, populations and natural resources within their communities. We discuss the success of this approach amidst the broader context of the application of WebGIS tools in this arena. Due to its flexible design and user-friendly interface, NJFloodMapper has been widely adopted by government and non-governmental agencies in the state to assess coastal flooding exposure and vulnerability in the aftermath of a recent destructive coastal storm. However, additional decision support tools are needed to help coastal decision-makers translate the place-based information into concrete action plans aimed at promoting more resilient coastal land use decisions.