---
name: Conversational interface
slug: conversational-interface
category: pattern
status: published
created: 2026-08-26T00:00:00.000Z
modified: 2026-08-26T00:00:00.000Z
definition: An interface operated in turns of language rather than by controls,
  where the transcript is the state and the only visible affordance is a box to
  type in.
aliases:
  - name: chat interface
    source: community
  - name: conversational UI
    source: community
  - name: chatbot UI
    source: community
tags:
  - ai
relations:
  contrastWith:
    - natural-language-interface
  variantOf: []
  partOf: []
  seeAlso:
    - chat-bubble
    - typing-indicator
    - prompt-input
implementations: []
sources:
  - title: "NN/g: chatbots"
    url: https://www.nngroup.com/articles/chatbots/
  - title: "IxDF: conversational UI"
    url: https://www.interaction-design.org/literature/topics/conversational-ui
demo: inline
exhibit: false
useWhen: the interface is a turn-by-turn conversation
---

Start with the fence, because two words are doing different jobs. A
[natural language interface](/natural-language-interface) is an input MODE: you ask for what
you want in words, and it can live anywhere, including inside an entirely ordinary screen
full of buttons. A conversational interface is a SHAPE: the transcript is the screen, turns
are the only unit of interaction, and there is nothing else to press. Every chat assistant is
both. A search field that understands a sentence is only the first.

The shape's defining problem is that it has no affordances. A screen made of controls
advertises what it can do just by existing, and a text box advertises nothing, so a reader
looking at a blinking cursor has to guess at both the capability and the phrasing. Everything
this pattern has learned about discoverability is an answer to that. Starter prompts in the
empty state, suggestion chips under the last reply, an opening turn that lists what is
possible in three concrete examples rather than in a claim about being helpful. Those are not
decoration around the conversation, they are its menu bar, and a build that ships without
them is asking every reader to invent the interface for themselves.

The transcript is doing more work than it looks like. It is the state, so there is no settings
panel to consult: what is true is whatever was last agreed, in words, some distance up the
scroll. It is the undo history, since correcting a turn means saying so rather than pressing
anything. It is the only record of the agreement, which matters enormously when the
conversation commits to something (a booking, a refund, a piece of code), and it is the
navigation, because scrolling back is how a reader returns to a decision. Design it as a
document, then: quotable, scannable, with each turn's own boundaries clear. The parts have
their own words, and the site holds them already: a turn is a
[chat bubble](/chat-bubble), the pause before a reply is a
[typing indicator](/typing-indicator), and the box is a [prompt input](/prompt-input).

The failure NN/g keeps measuring is worth memorising because it does not look like a failure
while you are building. A conversation is linear, so it works beautifully for the path the
team walked through, and collapses the moment the reader steps out of it: a question asked
two turns early, a change of mind, a request that needs three fields at once. Comparing five
options in prose is worse than a table. Picking a date in prose is worse than a calendar. The
strongest conversational interfaces are therefore not purely conversational at all, they hand
you a control at the point where a control is better, and the judgement about where that
point falls is most of the design work.