Graphs & Charts

Do This First

1. Start with the data table. Make sure the values exist in a readable table in Excel, Google Sheets, or another worksheet before you build the chart or graph.
2. Label the visual clearly. Add a descriptive title, category labels, axis titles, and units so users do not need to guess what the chart shows.
3. Add a text summary. State the trend, highest and lowest values, or the action point in nearby text or alt text.

Data and Summary

• Treat the chart as a visual summary and the data table as the full source.
• Write alt text that explains the pattern or takeaway, not a generic label such as 'sales graph.'
• For complex visuals, provide a longer note describing structure and conclusions.

Visual Differentiation

• Use labels, patterns, shapes, or direct annotations in addition to color.
• Keep contrast strong between data marks, labels, and the background.
• Prefer simple bar, line, or column charts over decorative 3D styles.

Complex Data

• Break dense dashboards into smaller sections with short written summaries.
• Explain filters, legends, or status categories in text.
• Use an alternate table or narrative summary for heatmaps and other dense visuals.

Common Problems to Catch

• Using color-only legends with no direct labels or patterns.
• Leaving axes unlabeled or omitting units.
• Packing too many pie slices or data series into one figure.
• Relying on the chart image when the exact values are not available elsewhere.