A data visualization system that automatically optimizes tick mark alignment to improve readability and conceptual accessibility of multiple graphs presented in a common display area. The data visualization system optimizes the tick mark alignment by normalizing the orders of magnitudes of the data sets and minimizing an objective function that balances tick resolution versus unused chart space on the common axis. The data visualization system may optionally color code the graphs and data ranges represented on the common axis to improve readability. Automatic scaling and tick mark alignment of the data sets is based on the display dimensions, which allows the graphs to be quickly re-optimized and redrawn on the fly. For example, the graphs may be automatically re-optimized and redrawn in response to display screen rotation, display area resizing, and display on different devices in a manner that appears to be effectively instantaneous to the typical user.