The fold

The word is borrowed from newsprint. A broadsheet is folded in half to be stacked on a newsstand, so only the top half of the front page is doing any selling, and the largest headline goes there. The web took the metaphor for the bottom edge of the browser window as a page first paints: everything above it arrives for free, and everything below it costs the reader a deliberate gesture. That is the whole idea, and it is worth keeping the two halves of the phrase distinct in speech, because “above the fold” is a place and “the fold” is the boundary that makes it one.

The complication is that a newspaper is folded in exactly one spot and a website is not. Phones, laptops, external monitors, split windows, and a reader who has enlarged their type all put the line somewhere different, so the fold is a distribution rather than a measurement, and any specific number written down for it (“640 pixels”, “the average is 900”) is a fiction with a decimal point. What survives the objection is the pattern behind it: attention is densest at the top of a page and thins out downwards, which holds whatever the viewport height turns out to be.

So the fold is a real gradient and a fake line, which is why the discourse settled into two slogans that are both half right. “Nobody scrolls” was wrong by about 1997 and was still being quoted a decade later to justify cramming an entire homepage into 600 pixels, which backfires reliably: a screen with everything on it emphasises nothing, and a band of content that happens to end exactly at the window edge creates a false bottom that reads as the end of the page and actually does stop people scrolling. “The fold is a myth” is the correction, and it goes too far in the other direction, because a reader still decides whether to continue based on what they can see, and the first screenful is where that decision gets made.

The practical version is a job description rather than a boundary. The first screenful has to say what this page is, offer the one thing most people came for, and make it visibly worth continuing, which usually means letting something be cut off by the bottom edge on purpose so the page reads as having more in it. Everything else is negotiable. The vocabulary has also followed the constraint down into performance work, where the content of the first viewport is what Largest Contentful Paint measures and what a hero region is competing for: it is why images up there need their space reserved by an aspect ratio box and why the ones below it are the candidates for lazy loading.