The creation of data visualizations has become easier as the skill barrier to our tools has decreased. However, adding interactivity, such as gestures for pan and zoom, still requires significant coding expertise. We introduce an open-source library-EasyPZ.js-for the creation of multi-scale (pan and zoom) visualizations across desktop and mobile devices. EasyPZ is fully customizable and extendable with flexible options for interaction design. For example, it is easy to choose gestures which are compatible with selection interactions such as clicking. EasyPZ can be enabled on any SVG-based visualization on the web with one line of code, or by simply clicking a bookmark without requiring commitment to code changes. With this library, we contribute ways for the visualization community to more easily author interactive multi-scale visualizations.