Chart color decisions
Chart Color Decisions: Values, Categories, Boundaries and Themes
Choose an exact chart question: missing versus zero, meaningful scale centers, stable categories, collisions, readable references, thresholds, touching fills or a dark surface.
Start with the information your reader needs. These guides supply complete original examples and distinguish numeric values, category identity and the actual colors that touch.
The example data are deliberately constructed. Replace them with documented real inputs before applying a classification or interpreting a result.
Keep values, status and scale meanings correct
Preserve unknown values, define a meaningful reference and make every numerical cutoff explicit.
Heatmap Colors: Keep Missing, Zero and Not Applicable Distinct
Keep numeric zero, not-observed and not-applicable states explicit. Six original records show how color choices and denominators change when those meanings are lost.
Diverging Heatmap Colors: Put Zero at the Intended Center
Choose an explicit meaningful center. Compare ordinary, symmetric and piecewise mappings for the same seven changes before calling a palette zero-centered.
Heatmap Legend Ranges: Make Every Boundary Unambiguous
Define exact inclusive and exclusive endpoints before assigning heatmap colors. Complete decimal and boundary examples keep the legend, code and displayed values consistent.
Keep category identity and comparisons visible
Follow the same category through filters, expose records hidden at shared coordinates and retain a comparison needed for the question.
Keep Chart Category Colors Stable After Sorting and Filtering
Keep category identity separate from sort position. An original keyed palette shows how the same categories retain their colors and shapes after filtering and sorting.
Overlapping Scatter Points: Show Counts Without Moving Coordinates
Count exact coordinate and category collisions before changing colors. Six original records show how to preserve locations and reveal records hidden by overlapping marks.
Highlight One Chart Series Without Hiding the Comparison
Keep any reference needed for the comparison visible. An exact four-period example separates visual emphasis, line identification and background contrast.
Check the actual adjacent colors and visible cues
Review touching stacked fills, labels and new surfaces; use the overview for the broader label, line, pattern and chart-data principles.
Stacked Bar Colors: Check Segment Edges and Labels Separately
Test the fills that actually touch, then test the labels. A complete 100-unit stack shows why white-background ratios alone miss internal edges.
Dark Chart Colors: Recheck Lines, Labels and Adjacent Surfaces
Recalculate the actual chart pairs when the surface changes. Complete light/dark role samples separate series visibility, ordinary text and fixed SVG export backgrounds.
Chart Colors Beyond Color Alone
Six original color/grayscale examples with labels, line styles, shapes, data tables and contrast guidance.
Use the original examples carefully
Each new guide supplies the complete original data or calculation inputs, a labelled SVG and explained decisions. Downloadable CSVs and text rules retain the stated units and boundaries. The color ratios are nominal sRGB calculations, not a physical display, user study or full accessibility certificate.
Inspect the actual color values before changing a foreground or background. Keep exact values and category names available in a static export.