Data-ink encodes values as the share of ink that represents data versus decoration. Edward Tufte, The Visual Display of Quantitative Information, 1983.
In reports, ads and assignments it fits auditing slides, dashboards and science figures. Skip it when a poster that must shout from three metres — ads may keep some junk on purpose.
Rules
- Rules 1 — Use the share of ink that represents data versus decoration as one channel, not two.
- Rules 2 — Direct labels beat a distant legend.
- Rules 3 — Do not hide zero. If you break the axis, say so.
- Rules 4 — Colour encodes category or magnitude, not both.
- Rules 5 — Put the claim in the title, not just “Data-ink”.
- Rules 6 — Source and period, even in small type.
Palette
- Palette 1 — Categories: distinct hues. Sequences: one hue, changing value.
- Palette 2 — Diverging: a neutral centre, emphasis at both ends.
- Palette 3 — One brand colour plus greys beats a rainbow.
- Palette 4 — Check contrast on a projector and in greyscale print.
Type
- Type 1 — Tabular figures for numbers. Do not pour body copy into the chart.
- Type 2 — Titles as sentences; axes as short nouns.
- Type 3 — For CJK, drop weight one step and leave tracking.
Data-ink: honour the share of ink that represents data versus decoration, and switch when a poster that must shout from three metres — ads may keep some junk on purpose.