Good chart design communicates data clearly without misleading or confusing viewers. Follow these principles to create effective visualizations.
Start Y-Axis at Zero
For bar charts, always start the Y-axis at zero. Truncating the axis exaggerates differences and can mislead. A bar that's twice as tall should represent twice the value. Line charts have more flexibility since they emphasize change, but be transparent about the axis range.
Use Color Meaningfully
Don't use random colors. Use color to group related data or highlight key points. Ensure sufficient contrast for accessibility. Avoid red/green combinations (colorblindness). Our API auto-assigns colors from a curated palette optimized for clarity and accessibility.
Label Clearly
Include a descriptive title that summarizes the insight, not just the topic ("Sales Doubled in Q4" vs "Quarterly Sales"). Label axes with units. Use a legend only when needed (multiple datasets). Avoid chart junk: unnecessary gridlines, 3D effects, or decorations that don't add information.