---
name: Detent
slug: detent
category: interaction
status: published
created: 2026-08-21T00:00:00.000Z
modified: 2026-08-21T00:00:00.000Z
definition: A position a control settles into and resists leaving, so a
  continuous drag or turn lands on discrete values that can be felt rather than
  read.
aliases:
  - name: discrete step
    source: community
  - name: stop point
    source: community
tags:
  - dragging
relations:
  contrastWith:
    - snapping
    - tick-marks
  variantOf: []
  partOf: []
  seeAlso:
    - microinteraction
    - knob
implementations:
  - system: hig
    name: Sheet detents
    url: https://developer.apple.com/design/human-interface-guidelines/sheets
sources:
  - title: "Apple Developer: UISheetPresentationController.Detent"
    url: https://developer.apple.com/documentation/uikit/uisheetpresentationcontroller/detent
  - title: "Apple HIG: Sheets"
    url: https://developer.apple.com/design/human-interface-guidelines/sheets
demo: inline
exhibit: false
useWhen: the position a control sticks at as you drag past it
---

The word is machinery. A detent is the spring-loaded ball riding in a groove that holds a
rotary switch at each of its positions, and what the hand feels is not the position but the
resistance on either side of it: it takes a little more force to leave than to arrive, so the
control sits where it was put. Software borrows the mechanism and the feeling. Give a
continuous gesture a set of detents and the value it produces stops being a fraction and
becomes one of five things, and the reader can count them with the hand instead of reading
them off a scale. That is why the term belongs to interaction rather than to layout: it names
a rule about how a control answers travel, not a mark on a surface.

Three neighbours look like this and are not. [Snapping](/snapping) is about alignment, pulling
a dragged object flush with a grid or another object's edge, so its stops are wherever the
scene happens to have edges; a detent's stops are properties of the control and are the same
every time. [Tick marks](/tick-marks) are printed, and printing is not force: a track can show
its scale and still accept every value between the notches, which makes the marks a ruler
rather than a catch. And a [knob](/knob) or a [slider](/slider) is the control itself, while a
detent is one thing that control may or may not do. The give-away in all three cases is what
happens as the pointer travels past a stop. If the value pauses and the readout refuses to
move for a few pixels, there is a detent there. If the handle merely passes a label, there is
not.

Two design duties come with them. The first is that the resistance has to be reported on some
channel the reader has, because a stop nobody can feel is just a rounded number: a phone pairs
each catch with a tick of [haptic feedback](/haptic-feedback), a pointer gets a visible step in
the readout and often a small jump of the handle, and either way the discreteness should be
legible without watching the number. The second is escape. A detent strong enough to be felt is
strong enough to make the values between the stops hard to reach, so a control that needs both
registers offers a way out: a slower drag, a modifier held down, or a typed field beside the
track for the exact number. Every value you cannot reach with the gesture has to be reachable
some other way.

The clearest production example is Apple's, which uses the word literally: a
[bottom sheet](/bottom-sheet) declares its heights as detents, the sheet's
[grabber](/grabber) is dragged between them, and letting go anywhere in between settles the
surface onto the nearest one. The same rule runs under [scroll snap](/scroll-snap) on a
scroller, under a [rotate gesture](/rotate-gesture) that clicks to level, and under the volume
control of every piece of audio software that wants to feel like hardware. It is a small,
old-fashioned idea, and it is most of what separates a control that feels made from one that
merely works.