Typography research
Serif or sans-serif?
Sans-serif typefaces are generally considered more legible at small sizes and on screens. There is a long-standing belief that serif typefaces read better in print, but little evidence supports it. Choosing a sans-serif for screen use therefore doesn’t make printed visuals less legible.
Comparing the Windows sans-serifs
Of the five sans-serifs on most Windows machines, all meet the availability and legibility criteria, but only Aptos and Calibri also meet the number criteria.
| Aptos | Calibri | |
|---|---|---|
| Weights | Light, regular, semibold, bold and more | Light, regular and bold |
| Width | Wider | Narrower, so more text fits without shrinking it |
| Office default | Current default | Default until 2023 |
Calibri wins when space is tight, and when consistency with an existing brand that uses it matters. Aptos wins on its range of weights.
Figures for numbers
Charts display numbers more than ordinary text does. Three properties matter:
- Lining figures sit on the baseline and share one height, so labels look even.
- Tabular figures all have the same width, so columns of numbers line up.
- Multiplexed typefaces keep digits the same width across weights, so bolding a label doesn’t reflow the layout.
In CSS, font-variant-numeric: tabular-nums lining-nums; turns on the first two in fonts that support them.
Sources: Datawrapper, Fonts for data visualization; data.europa.eu, Serif vs sans serif. See references.