How To Choose The Right Typography For UX Design?

Choosing a typeface is one of the first design decisions that affects both reading comfort and brand credibility. A precise balance of legibility, visual hierarchy and guidelines directly influences key site metrics – from a lower bounce rate to a higher conversion rate. Let’s look at the criteria worth considering when selecting a font and at practical steps that keep a site fully accessible and fast on every device.

A UX designer’s priority is to ensure quick perception and complete legibility of content. Research by the Interaction Design Foundation shows that readable typography minimises cognitive load and guides the eye along the intended scanning path, raising conversion rates by several percentage points compared with an identical layout that uses an unsuitable typeface or size.

When choosing a font we start with type classifications (serif, sans serif, slab, script, display, monospaced) and their predicted role in the interface. Nielsen Norman Group recommends a clear split of roles: a neutral base font for long‑form reading and, optionally, a decorative face used in highlighted headings. The two must differ enough in x‑height and contrast so they do not compete for attention.

The starting font size should fall between 16 – 18 px for body text and 24 – 36 px for headings, while retaining the ability to scale to 200 % without loss of functionality, as required by WCAG 2.2 (criterion 1.4.4). Using relative units (rem, em) instead of px allows users to adjust the font size smoothly in the browser, which significantly improves the experience of people with low vision.

The most effective hierarchy is created by combining size differences (at least 1.25×), weight (regular → bold) and the colour contrast between text and background.

For normal text the contrast must be at least 4.5 : 1, whereas for enlarged text (≥ 24 px or ≥ 19 px bold) it may drop to 3 : 1. In practice, instead of using many typefaces, one family with at least four weight variants is enough; this avoids excessive cognitive load and the transfer cost of multiple font files.

So how should fonts be combined in line with UX principles? The safest approach pairs a font with a strong personality (e.g. a decorative display typeface in the hero heading) with a neutral sans‑serif in the body text. The roles must remain consistent throughout the system and be defined in the design documentation. Mixing fonts without a clear assignment to components undermines brand credibility. Both fonts must also support the full character set and keep the glyphs for the digit 1, the uppercase I and the lowercase l clearly distinguishable.

Besides size and contrast, WCAG 2.2 (SC 1.4.12) requires that when a user manually increases spacing (line‑height ≥ 1.5 × font‑size, letter‑spacing ≥ 0.12 em) the content remains fully accessible.

U.S. Section 508 in turn specifies the minimum physical character height for displays (4.8 mm, roughly 12 px at standard DPI) and forbids italics in accessibility messages. Remember that legal compliance is the foundation, but truly inclusive experience demands testing with users who rely on screen readers, OS magnifiers or high‑contrast mode.

To choose a font for a website effectively, it is worth using the tools that are readily available. For example:

• Google Fonts Knowledge – a compendium on selecting, pairing and loading typefaces.
• Font Pairing Playground (NN/g) – an interactive environment for evaluating contrast and type classes.
• WebAIM Contrast Checker – a quick way to verify text contrast ratios.
• Typewolf – a daily‑updated gallery of font implementations in real projects.
• CLI subsetter pyftsubset – a tool for sub‑setting fonts to the WOFF2 format.

Choosing a font is a process that blends hard accessibility requirements, business goals and brand subtleties. A well‑thought‑out typographic decision increases user comfort, improves loading‑speed metrics and strengthens brand recognition – all achievable by applying the clear criteria and tests described above.