Timed Text Style Guide

1.0 About

This document describes UTK Libraries’ style guide for creating closed captions and subtitle files for audio and video. It is largely informed by the Netflix Timed Text Style Guide: General Requirements.

2.0 Duration

The duration of a subtitle event should be between 5/6 (five-sixths) of a second (e.g. 20 frames for 24fps) and 7 seconds.

3.0 File Format

For closed captions and subtitles, use webVTT (.vtt).

4.0 Glyphs

Only text or characters included in the NETFLIX Glyph List can be used.

5.0 Line Treatment

5.1 General Rules

Text should usually be kept to one line, unless it exceeds the character limitation. Text should never exceed 2 lines.

5.2 Character Limitation

Lines should never exceed 42 characters. This includes spaces and punctuation.

5.3 Rules for 2 Lines

When a subtitle event exceeds the character limitation defined above, it should be broken into two lines. This section describes the rules for breaking a subtitle event into two lines.

5.3.1 Basic Line Break Rules

The first line should be broken at a specific point rather than at the character limit. Valid break points include:

after punctuation marks
before conjunctions
before prepositions

5.3.2 Nuanced Line Break Rules

A line break should not separate:

a noun from an article
a noun from an adjective
a first name from a last name
a verb from a subject pronoun
a prepositional verb from its preposition (e.g. agree with, approve of)
a verb from an auxiliary (e.g. have been), reflexive pronoun (e.g taught myself) or negation (e.g. hardly ever, does not)