There are a variety of ways to quantify cancer survival with each measure having advantages and disadvantages. For example, relative/net survival is useful for making fair comparisons between population groups and over time, but is of less relevance to clinicians or patients. The differences between the various measures and how they should be interpreted has led to confusion among scientists, the media, health care professionals and patients. We have developed an online interactive tool to help improve the understanding of a variety of cancer survival measures and how these vary between patients. Its primary purpose is to function as an aid in the interpretation of a variety of commonly reported, important and more complex cancer survival measures that are available from fitting statistical models. The interpretation is facilitated through the use of dynamic interactive graphics available using an online interactive tool. The interactivity improves understanding of these measures and how survival or mortality may vary by age and sex. Routine measures of cancer survival are reported, such as net and all-cause survival. In addition, individualised estimates using crude probabilities are often more appropriate for patients or health care professionals. The results are presented in a variety of ways, including graphs, “people charts”, tables and descriptive text using natural frequencies. All results are updated immediately when using drag bars, drop-down menus or radio buttons. This immediate feedback together with the simple text descriptions leads to both better understanding of individual risk and the differences between the various measures. The online tool is in final testing using English data for a range of cancer sites. The tool is available at www.interpret.le.ac.uk. We have plans to further develop the interactive tool by incorporating data from different countries and from statistical models that incorporate more disease characteristics (e.g. stage, grade and tumour size).