Inter and SF Pro are the AI defaults. They are well-designed, neutral, and so widely used that they have become invisible. That's not a virtue — it's a tell.

What "default" looks like

If a landing page uses Inter Variable from Google Fonts at the standard weights with the standard tracking, the page is competing with every other AI-generated page that did the same thing. Even if the layout is otherwise good, the typeface signals "default."

Better choices

PangramPangram — Object Sans, Pangram Sans, Pangram Sans Rounded. Free for personal use.
Displaay — Grato, Migra, Neulis. Editorial energy.
Grilli Type — GT Walsheim, GT America, GT Maru. Swiss, considered.
Søren Sprogø — open-runde (free). Geometric with personality.
Vercel Geist — Geist Sans, Geist Mono. Now widely used, but still better than Inter.
GitHub Mona — well-tuned, less common.

The single-weight rule

For a project's first iteration, buy or download one weight of a paid font (the variable family if you need ranges). Use it for headings, body, everything. Pair with the system default for fallback.

This is faster, cheaper, and produces better hierarchy through size and spacing alone. Add weights only when a real need arises.

When to apply

Anytime you reach for Inter, SF Pro, Roboto, or "system-ui" on a marketing page — stop and pick something else. For in-app product UI, Inter / SF Pro are fine (they're optimized for screen UI), but if you do use them, you've used your one default. Don't also use the default colors and the default Lucide icons.

Gotcha

Custom typography on tiny UI text (10–12px) often loses legibility. Geometric sans like Walsheim or Pangram look great at 14px+ but mush at 10px. Test at every size you actually use. Inter exists because it's hyper-legible at 12px — sometimes that wins.

See also line-length-tracking for the rules around how to use whichever font you pick.

Sources

guidelines.sh — "Inter/SF Pro are AI defaults; explore PangramPangram, Displaay, Grillitype."
Emil Kowalski / Vercel Geist — single-weight workflows.