Nobody looks at a page and thinks “the leading is too tight”. They think it looks cheap, and they move on. Typography is the part of design that works entirely below the level of conscious attention, which is exactly why getting it wrong is so expensive and getting it right is so cheap.
Almost none of what follows is a matter of taste. These are the ten things that reliably separate work that looks made from work that looks assembled, and every one of them takes about a minute to fix.
1. Using more than two typefaces
Three fonts on a page is the single most reliable sign that nobody was in charge. The instinct behind it is generous: the headline wants presence, the body wants to be readable, the caption wants to feel different. But difference is not the same as contrast, and three voices talking at once is just noise.
Pick one typeface with a decent range of weights and use it for everything. If you want a second, make it genuinely different in kind, not merely different in name: a strong display face for headlines against a quiet workhorse for text. Two families, four or five weights between them, and you have more variety than you will ever need.
2. Faux bold and faux italic
When you press the bold button and the font has no bold weight, the software fakes it by smearing the letters outward. Italic gets faked by slanting the uprights. Both look exactly like what they are: a shape that was never drawn, stretched into an approximation.
Real weights are drawn separately. The bold of a good family is not the regular with more ink, it has different proportions, tighter counters, adjusted spacing. If a family you like has only one weight, that is a reason to choose a different family, not a reason to fake it.
3. Lines that run too long
The eye loses its place on the return sweep when a line runs past roughly seventy-five characters. It has to hunt for the start of the next line, and after a few paragraphs of hunting the reader quietly gives up and calls the text boring.
Somewhere between forty-five and seventy-five characters per line is the range that has survived five centuries of people testing it. On a wide screen that usually means the text column should not be as wide as the container it sits in. Give it a maximum width and let the white space happen.
4. Leading that fits the software, not the text
Default line spacing is set for a font size nobody is using at a line length nobody has. As type gets larger, it needs proportionally less space between lines; as lines get longer, they need more.
A rough working rule: body text is comfortable at around 1.5 to 1.7 times the font size. A large headline usually wants 1.0 to 1.2, because at that size the gap between lines reads as a gap between thoughts. If a heading looks like two separate statements, the leading is too loose.
5. Justified text without hyphenation
Justified columns look tidy in a specimen and terrible in practice, because forcing both edges straight means the spaces inside each line have to stretch. Do it without hyphenation and you get rivers: pale channels of white running vertically through the paragraph, which the eye follows instead of the words.
On the web, set text ragged right and stop thinking about it. In print, justify only if you also hyphenate, and then actually look at the result rather than trusting it.
6. All caps for anything longer than a label
We do not read letter by letter. We read the shapes of whole words, and a large part of that shape comes from ascenders and descenders, the strokes that stick up and hang down. Set a sentence in capitals and every word becomes the same rectangle.
Capitals are excellent for a short label, a button, an eyebrow above a headline. Beyond about five words they slow reading measurably. If you set them, add letter spacing, because capitals were never designed to sit as close together as lowercase.
7. Letter spacing applied in the wrong direction
The general rule runs opposite to what most people do: large type wants tighter spacing, small type wants looser. A big headline set at default spacing looks slack, with gaps between letters that read as gaps between words. Caption text at default spacing often looks cramped.
Tighten headlines slightly, by a fraction of the letter width, until the word reads as one object. Open up small caps and labels a little. Never touch the spacing of body text.
8. Gray text that is gray for no reason
Somewhere in the last decade, light gray on white became shorthand for sophisticated. It is mostly shorthand for unreadable on a phone in daylight.
Contrast is measurable, not a matter of feel. Body text should clear a ratio of 4.5 to 1 against its background, and large text 3 to 1. If you want text to recede, make it smaller or lighter in weight, not paler. Most editors, including the one described on this site, can measure a contrast ratio for you, which is faster than arguing about it.
9. Headings that do not form a scale
When a page has a 32 pixel heading, a 30 pixel heading and a 28 pixel heading, none of them reads as more important than another. The reader cannot see the hierarchy because the hierarchy is not there.
Build a scale with real steps: pick a body size, then multiply. Something like 1.25 or 1.33 between each level gives a set of sizes that look deliberate. Three levels are usually enough. If you need a fourth, ask whether the page really has four levels of meaning.
10. Punctuation typed instead of set
The straight quote mark on your keyboard is not a quotation mark. It is a typewriter compromise from an era with limited keys, and it appears in professional work roughly never. The same goes for using a hyphen where the sentence needs a longer dash, and for three full stops in a row where an ellipsis belongs.
Most software will fix quotes automatically if you let it. The rest is a habit worth building, because these marks are small and constant, and they signal care in a way readers register without being able to name it.
What to do with all this
Do not try to hold ten rules in your head while designing. Instead, use them as a checklist afterwards. Finish the layout, walk away for five minutes, come back and go down the list: how many typefaces, is anything faked, how long are the lines, does the spacing fit the size, is the contrast real, do the headings step.
Most designs fail two or three of these. Fixing those two or three is usually the difference between something that looks homemade and something that looks like it was made on purpose. It costs a minute, and it is the highest return minute in the whole job.
