Color Blindness

---
name: data-visualization-color-blindness
description: 'Sub-skill of data-visualization: Color Blindness (+3).'
version: 1.0.0
category: data-analytics
type: reference
scripts_exempt: true
---

# Color Blindness (+3)

## Color Blindness


- Never rely on color alone to distinguish data series
- Add pattern fills, different line styles (solid, dashed, dotted), or direct labels
- Test with a colorblind simulator (e.g., Coblis, Sim Daltonism)
- Use the colorblind-friendly palette: `sns.color_palette("colorblind")`


## Screen Readers


- Include alt text describing the chart's key finding
- Provide a data table alternative alongside the visualization
- Use semantic titles and labels


## General Accessibility


- Sufficient contrast between data elements and background
- Text size minimum 10pt for labels, 12pt for titles
- Avoid conveying information only through spatial position (add labels)
- Consider printing: does the chart work in black and white?


## Accessibility Checklist


Before sharing a visualization:
- [ ] Chart works without color (patterns, labels, or line styles differentiate series)
- [ ] Text is readable at standard zoom level
- [ ] Title describes the insight, not just the data
- [ ] Axes are labeled with units
- [ ] Legend is clear and positioned without obscuring data
- [ ] Data source and date range are noted