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Weight Watcher

A free typography game: match a hidden font weight, size or line height by eye in six rounds and see the real value, with a rule of thumb for each.

What it does

  • Six rounds: two on font weight, two on size and two on line height
  • A target sample with a hidden value and a sample of yours to match
  • Scored by how far off you are, with size judged as a percentage
  • The real value and a practical rule after every round

FAQ

Which font weights should I use?

Few and clearly different: 400 for body text, 500 for labels and buttons, 600 or 700 for headings. Two weights side by side should differ by at least 200.

What line height is best for body text?

Between 1.4 and 1.6 for paragraphs. Headings are tighter, around 1.1 to 1.25, and longer lines need more room than short ones.

How do I choose a type size scale?

Make each step noticeably bigger than the last, about 1.2 times or more, such as 14, 16, 20, 24, 32, 40, 48. Fewer sizes make a stronger hierarchy.

📖 Font weight, size and line height: how to choose them

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