---
name: Miller columns
slug: miller-columns
category: layout
status: published
created: 2026-08-21T00:00:00.000Z
modified: 2026-08-21T00:00:00.000Z
definition: A browsing layout of side-by-side columns where selecting an item in
  one column fills the next with its children, keeping the whole path visible.
aliases:
  - name: column view
  - name: Finder columns
  - name: cascading lists
tags:
  - navigation
relations:
  contrastWith:
    - cascader
    - drill-down-navigation
  variantOf: []
  partOf: []
  seeAlso: []
implementations: []
sources:
  - title: "Wikipedia: Miller columns"
    url: https://en.wikipedia.org/wiki/Miller_columns
demo: inline
exhibit: false
useWhen: browsing a deep hierarchy with the path kept visible
---

Miller columns turn depth into width. Each column is one level of a hierarchy, selecting an
item fills the column to its right with that item's children, and the set slides sideways as
the path gets longer. The layout is named after Mark Miller, who described it in the
mid-1980s, and most people have met it as column view in the macOS Finder, which inherited it
from NeXTSTEP. The whole idea rests on one property: at any moment, every level of the path
you are standing on is on screen at once, and so are the siblings you could have chosen at
each of those levels.

That property is what separates it from the two layouts it is usually weighed against. A
[treeview](/treeview) nests in place, expanding a node downward so the entire tree, including
branches nowhere near your path, can be open at the same time. [Drill down
navigation](/drill-down-navigation) does the opposite and shows one level at a time, replacing
the view as you descend, which is cheap on a narrow screen and costs you all context. Miller
columns sit exactly between them: only the current path is expanded, but all of it is, so
retargeting one level up is a single click on a column that is already in front of you rather
than a collapse, a back gesture, or a hunt through an outline.

The last column is usually not a list at all. Select a leaf and the final column becomes a
preview of it, which is why the pattern feels like [list detail](/list-detail) with the
breadcrumb built into the layout. It is worth being deliberate about that column, because it
is the only one that answers "is this the thing I wanted" without another click.

The costs are real and mostly about width. Columns are typically a fixed size, so long names
truncate no matter how much room the window has, and a deep path eventually forces horizontal
scrolling that some readers find genuinely disorienting. The layout wants a wide window, which
is why it is rare on phones and why the same file browser that offers column view on a desktop
falls back to drill down on a handset. It also needs a keyboard model people can guess: left
and right arrows move between levels, up and down move within one, and anything else will be
learned by nobody. Reach for it when the hierarchy is deep, wide, and genuinely browsable
rather than searched, and when a reader will move sideways across it as often as down it.