How "Deep Time" was made

A single scrollable page that is 4.54 billion years tall, drawn strictly to scale. One idea, executed literally: every geologic boundary sits at its true proportional depth, so the emptiness of the Precambrian and the thinness of the human sliver are not rhetoric — they are the actual geometry of the page.

What it demonstrates

That the most persuasive data visualisation is often the one that refuses to cheat. Almost every timeline of Earth compresses the first four billion years to make room for the parts we care about; that compression is the lie that makes deep time feel comprehensible and therefore wrong. This page removes the compression and lets the scale do the arguing. It is built from one constant and a table of ratified dates — no charting library, no scroll animation framework.

The techniques, honestly named

• One linear constant. The whole column is age × 5 pixels from the top: five pixels per million years, so the page stands 22,700 px tall. Every boundary, event and label is positioned by the same function. There is no easing, no log scale, no "detail inset" — the honesty is the feature.
• Ratified boundary ages. The period bands come from the International Chronostratigraphic Chart v2024/12 (International Commission on Stratigraphy). Base ages are stored as data and both drawn and printed in the footer table, so the picture and the citation can never drift apart.
• A stratigraphic rail. The coloured core column is 27 absolutely-positioned bands, each a period or (in the Precambrian) an era, tinted toward the ICS chart's own palette. A band only prints its name when it is tall enough to hold the rotated label, which is why the thin young periods stay clean.
• A live depth gauge. A fixed readout maps a reference line at 42% of the viewport to an age, and names the eon, era and period there. Overlapping names are de-duplicated, so the Hadean — which has no era or period subdivisions — reads simply "Hadean" rather than three times over. Updates are throttled to one requestAnimationFrame per scroll.
• The human sliver, to scale. The genus Homo spans the top 14 pixels; all of recorded history is about two-hundredths of one pixel and is drawn nowhere, because it is thinner than a screen can render. The page says so plainly instead of faking a marker.

Reduced-motion visitors lose only the smooth-scroll behaviour; the page is otherwise static and fully keyboard navigable, with a skip link straight to the sources. No canvas, no WebGL — just layout, so it is fast and degrades to nothing.

Recreate it