Designing Charts: Gridlines

Gridlines can be a useful addition to data visualizations, as they help to enhance the readability and understanding of the information being presented.

When deciding whether or not to use gridlines in a chart or graph, you should consider the following factors:

• Complexity of the data: If your data is complex with many different data points or categories, gridlines may be beneficial in helping your audience understand the relationships between these points. For instance, a line chart with multiple series may benefit from gridlines, making it easier to compare values across categories.
• Audience familiarity: If your audience is unfamiliar with the subject matter or the data being presented, gridlines can provide valuable context and make it easier for them to grasp the main trends or insights. A good example is when presenting financial data to people who may not have a strong background in finance. Gridlines can help them understand fluctuations in the numbers more easily.
• Precision of the data: If your data requires high precision, gridlines can help by providing a visual reference for exact values. In this case, it’s essential to ensure that the gridlines align with the axis labels so they effectively serve as a guide for the viewer. For example, if you are showing a chart about temperature changes over time, gridlines can help users see the exact degrees at different points.
• Design balance: While gridlines can be helpful, they can also create visual clutter if overused. When deciding whether to use them, consider whether they would make your chart more readable or add unnecessary noise. You want to strike a balance between providing enough visual aid without overwhelming the viewer.
• Use a light color for gridlines: Choose a light color that doesn’t distract from the main data and complements the overall design of your visualization.
• Use consistent spacing: Ensure that the gridlines are evenly spaced across the chart to make it easier for viewers to gauge relative distances and identify patterns.
• Limit the number of gridlines: Too many gridlines can make your chart appear cluttered and confusing, so use them sparingly and only where necessary.

In summary, gridlines can be useful in data visualizations, but only when they enhance the comprehension of the information being presented. Consider the data’s complexity, your audience’s familiarity, the precision required, and the overall design balance when deciding if gridlines are appropriate for your chart.