---
name: Sign language interpretation
slug: sign-language-interpretation
category: accessibility
status: published
created: 2026-08-21T00:00:00.000Z
modified: 2026-08-21T00:00:00.000Z
definition: A signed track alongside video, presented as an inset or a companion
  stream, for readers whose first language is a sign language rather than the
  written caption text.
aliases:
  - name: signed video
    source: community
  - name: interpreter inset
    source: community
  - name: sign language (prerecorded)
    source: wcag
tags:
  - i18n
  - media
  - wcag
relations:
  contrastWith:
    - captions
  variantOf: []
  partOf: []
  seeAlso:
    - video-player
implementations: []
sources:
  - title: "WCAG 2.2: Sign Language (Prerecorded)"
    url: https://www.w3.org/TR/WCAG22/#sign-language-prerecorded
demo: inline
exhibit: false
useWhen: captions are not the reader's first language
---

Criterion 1.2.6 asks for sign language interpretation of prerecorded audio, and it sits at level
AAA, which is why most teams have never had to think about it. The reason it exists is the part
worth understanding, because it is not obvious from the outside: a sign language is a language of
its own, not a transcription of the spoken one. British Sign Language and American Sign Language
have their own grammar, their own idioms, and no genetic relationship to English or to each other.
Facial expression and the space in front of the signer carry grammatical meaning, which is why an
interpretation is a translation and not a relabelling.

That is what [captions](/captions) cannot fix. Captions present the spoken words in written form, so
for a reader whose first language is a signed one they are a second language, read at speed, while
also watching the picture. Many Deaf readers are entirely comfortable with that and many are not, in
the same way that subtitles in your third language are technically sufficient and quietly exhausting.
Reading age in the written language of the surrounding country is, on average, lower among people who
have signed from birth, which has nothing to do with ability and everything to do with the written
language being learned second, largely through the eye.

Presentation is where designs usually go wrong. The common pattern is a small inset in a corner of
the [video player](/video-player), and the common failure is making it small enough to be free.
Hands move fast, fingerspelling is fine detail, and the face is grammar, so a thumbnail that keeps
the picture uncluttered has thrown away most of the language. Better provisions give the signed
track real size: a companion stream the same size as the video, a picture-in-picture the reader can
scale and move, or a version of the whole video with the interpreter composed in at a usable size.
Whatever the arrangement, the reader chooses it, and the choice belongs in the same place as the
caption and [audio description](/audio-description) controls rather than on a separate page.

Two practical notes. Production cost is real, so it lands first where it pays best: safety
information, legal and medical content, anything a public body publishes, and evergreen video that
will be watched for years. And an interpreter is a person, so their track has its own needs: even
lighting, a plain background, contrasting clothing, no cropping at the wrists, and a shot wide enough
for signs that use the whole signing space. Getting the framing wrong is the quickest way to spend
the entire budget on a track nobody can read.