Chart Your Heart Out

The Google Chart API is simple to use and easy to integrate into web applications. As shown here, you can use the API immediately – just embed a static link in your web page and let the browser request and render a chart each time the page is drawn.

To speed page rendering, you can request and cache the chart image on your own server, recreating the chart only when the underlying data changes. In addition to providing better efficiency, this technique better protects your raw data. A visitor to your site cannot "View Source" and copy the URL.

Of course, you can also mix the Google Chart API with AJAX techniques to modify charts on the fly in response to user input. Chart Maker [6] is a basic but effective demonstration of dynamic charting; others have used the Google Chart API to implement a loan calculator and executive dashboards.

Of course, Google Chart is often slower than charting tools that run on the desktop, such as Apple Numbers or Microsoft Excel. These latter applications use native drawing engines and do not require an Internet round-trip to transmit data and download a large graphic image. However, Google Chart is a free application that is available from anywhere. If you are serious about using Google Chart in a production setting, pre-flighting and caching can greatly improve response time.