Comfortable UI Starts Here: Font Sizes, Spacing, and Padding That Just Feel Right

Backed by UX research and real-world UI standards

Design that feels comfortable isn't just about aesthetics.

True comfort in digital environments comes from clarity, visual rhythm, and effortless interaction.

That means:
- Fonts that are readable without strain
- Spacing that guides the eye, not clutters it
- Padding that feels balanced—not crammed or empty

Let’s break down what comfortable UI really means, based on actual UX research, accessibility standards,

and design systems like Apple HIG and Google’s Material Design.

Font Size: The Core of Readability

According to the Nielsen Norman Group and MIT’s vision research, font size and line height directly affect reading speed and visual fatigue.

• Too small? Users strain and give up

• Too large? The eye loses its flow

What’s the Ideal Font Size?

• English body text: ~16px (≈1rem) shows the highest reading speed

• Korean text: ~14–16px, optimized for Hangul character density and stroke structure

Recommended Font Sizes by Platform

Sources: Apple HIG, Material Design Typography, WCAG

• Apple HIG – Typography Guidelines

• Material Design Typography Scale

Margin & Padding: Breathing Room Matters

Humans are wired to group things visually. That means spacing is more than decoration—it shapes perception.

• Inconsistent spacing = chaos

• Overcrowding = fatigue

• Too much white space = looks empty

Ideal Layout Metrics

How Real Brands Apply These Standards

Let’s look at some leading digital products to see how they implement comfortable UI at scale:

Google (Material Design)

• - Body: 16px (Roboto / Noto Sans KR)

• - Headlines: H1 32px / H2 24px

• - Card padding: 24px (vertical) / 16px (horizontal)

• - Section spacing: ~64px

• - Button: 48px tall, 12px 24px padding

Apple (HIG)

• - Body: 17pt (~16px)

• - Headings: 28–34px

• - Buttons: 44px minimum height

• - List spacing: 16–20pt

• - Mobile first spacing emphasis

Medium

• - Body: 21px with 1.5–1.6 line height

• - Title: 42px

• - Paragraph spacing: 24px

• - Page margins: ~96px on desktop

Notion

• - Body: 16px (system font)

• - Headings: H1 32px / H2 24px / H3 20px

• - Block spacing: 16–24px

• - Page padding: 96px (desktop) / 24px (mobile)

Airbnb

• - Card spacing: 32px

• - Card padding: 24px

• - Title fonts: 30–36px

• - Body: 16px / Secondary text: 14px

Summary: UI That Feels Comfortable Is Measurable

Design Isn't Just About Beauty—It’s About Comfort

When your users say a design “feels right,” it usually means it aligns with how the eye wants to move,

how the brain wants to read, and how the hand wants to click.

Start with these measurable standards. Then iterate with real user feedback.

Designing with comfort in mind is not guesswork—it's a craft built on data.