Numio gives you up to three font slots — primary, secondary, and number — so headings, body text, and numeric values can each have their own typeface.
All three live in the Style tab in the editor's left navigation, under the theme and color controls.
The three font slots
Primary Font
Always available. This is the main typeface for your project — titles, headings, and most text. Pick any font from the searchable font picker.
Secondary Font
The typeface for supporting body copy and descriptions. It appears whenever the project is not a calculator in single-page (side-by-side) view — that is, on the two-screen layouts and on non-calculator projects.
Next to the Secondary Font picker is a small text-transform toggle:
- Aa — normal sentence case.
- AA — uppercase, with letter spacing (caps style).
Use the caps option for eyebrow-style labels and the normal option for regular body text.
Number Font
The typeface for numeric values, such as calculated results. It appears on the two-screen layouts (Color Bar and Duotone). If you don't choose one, numbers use a monospaced default (IBM Plex Mono), which keeps figures aligned.
What single-page view changes
In a calculator using Side-by-side (single-page view), the font controls are simplified:
- The Secondary Font and Number Font pickers are hidden.
- Both fall back to the Primary Font, so the whole calculator uses one typeface.
- The secondary-font text-transform toggle is hidden.
If you want distinct secondary and number fonts, switch the theme to Color Bar or Duotone. See Themes and layouts and Single-page (side-by-side) view.