---
name: Smart defaults
slug: smart-defaults
category: pattern
status: published
created: 2026-08-21T00:00:00.000Z
modified: 2026-08-21T00:00:00.000Z
definition: Prefilling a choice with the answer most people in this situation
  want, so the common case needs no work and every other case is still
  reachable.
aliases:
  - name: good defaults
    source: ui-patterns
  - name: sensible defaults
    source: community
  - name: prefilled values
    source: community
  - name: recommended option
    source: goodui
tags:
  - forms
relations:
  contrastWith:
    - redundant-entry
    - preselected-opt-in
  variantOf: []
  partOf: []
  seeAlso:
    - forgiving-format
implementations: []
sources:
  - title: "UI Patterns: Good Defaults"
    url: https://ui-patterns.com/patterns
  - title: "GoodUI: Try Smart Defaults instead of asking to do extra work"
    url: https://goodui.org/
demo: inline
exhibit: false
useWhen: the form arrives already answered the way you would have
---

A default is the answer the interface gives on the reader's behalf before they have
said anything. It is not a neutral act. Defaults are the most powerful control on any
form, because most people accept them: Eric Johnson and Daniel Goldstein's 2003 study
of organ donor registration found participation rates differing by tens of percentage
points between countries whose only meaningful difference was whether the box started
ticked. Whatever a form starts with is what most of its answers will be. A smart
default is the deliberate use of that fact in the reader's favour, filling in what the
situation already implies so that the common case is a single tap and every other case
is one gesture away.

Good defaults come from three places. The reader's own context supplies most of them:
locale, timezone, the address on file, the card used last time, today's date in a date
field. Population data supplies the rest: if four in five people pick standard
delivery, standard delivery is the honest starting point. And where neither knows, the
default should be the least destructive option, since an accepted default that does
nothing is recoverable and one that spends money is not. Saying why on screen turns a
guess into information: a small "Most common" beside the preselected shipping method
tells the minority who need something else that the form is not merely assuming, and
it costs the majority nothing.

The line between this and the dark twin is direction, not mechanism. A smart default
serves the reader's likely intent; a **preselection** serves the seller, and it is
catalogued as a [dark pattern](/dark-pattern) for good reason. Three rules keep the
two apart. Never default to spending more, sharing more, or consenting to more:
consent under the GDPR has to be an affirmative act, which is why a pre-ticked
marketing box is a compliance problem and not a design preference. Never hide the
default: a prefilled field a reader can see is one they can correct, while an
assumption made silently is discovered at the worst moment. And changing it has to be
a single, visible gesture, never a trip into a settings screen.

Two failure modes remain even when the intent is good. A default that is right for the
majority is wrong for someone, so the exception path deserves the same care as the
happy one: an inferred country that cannot be changed until a page reloads is worse
than an empty select. And some fields have no defensible default at all. A name, a
password, a medical answer, a legal declaration: prefilling those does not save work,
it invites a person to agree to something they did not read.