Punctuation does extra work in subtitles
In a printed book, punctuation guides the reader through grammar. In subtitles it also has to stand in for sound: pauses, trailing off, interruption, surprise. At the same time, every mark takes up space and attention. The result is a set of habits that follow ordinary writing with a few adaptations.
Practices differ between guides, languages and clients. What follows describes common approaches, not rules that everyone follows. Where a project has its own guide, use it.
The basics
Subtitles generally use standard punctuation for the language: periods at the end of sentences, commas for natural pauses, question marks for questions, and so on. A few points often come up.
- Sentences usually start with a capital letter and end with a mark, except where a sentence continues in the next cue, which some guides handle differently.
- Commas and periods help the reader find structure, so they should be kept where they clarify.
- Exclamation marks are used sparingly. One is enough; strings of them look noisy and rarely add emphasis.
- Quotation marks are used for quoted speech or for words quoted within a line. Single and double quotation marks differ by language and region, so follow the convention of the target language.
- Straight versus curly quotes is a technical matter in files, and mismatched characters can show up as errors, as covered under character encoding.
Ellipses and dashes
Three dots, called an ellipsis, commonly signal speech that trails off, hesitates or is incomplete. A dash at the end of a line often signals speech that is cut off by interruption. A dash may also join a sentence that continues across cues. Using the same signal in the same way every time is more important than which one a guide picks.
Another use of dashes is to indicate a change of speaker, usually a dash at the start of each person’s line in a two-speaker cue. That is a different function from interruption, and it is the main topic of the article on speaker identification, so the same mark can mean different things in different places. Good style guides spell this out.
Italics: when slanted text is used
Italics are the most common special formatting in subtitles. Typical uses include:
- Voices that are not physically present in the scene, such as a narrator, a voice on the telephone, a radio or television voice, or a character speaking from off screen.
- Thoughts or internal monologue, in some guides.
- Titles of works, such as films, books and songs, in guides that follow ordinary print style.
- Foreign words, particularly when the audience would not expect them, as discussed under untranslated speech.
- Emphasis on a particular word, used carefully so the effect is not lost.
- Song lyrics, in some guides, sometimes combined with a musical note symbol; see song lyrics.
Not all guides use italics for all of these. Some avoid italics altogether, for example when a platform does not render them reliably, or when italic text is harder to read on a small screen. Check how your player or file format handles italics before relying on them. Technical support for formatting is a feature of caption styling.
Emphasis without overdoing it
Emphasis in speech comes from tone and volume, which text cannot carry. Capital letters are sometimes used for shouting, and italics for stressed words, but they work best rarely. If every second line contains emphasis, none stands out. If the context already makes the stress clear, leave it unmarked.
All capitals for whole sentences are generally avoided in ordinary dialogue because they are harder to read than mixed case. They are sometimes used for on-screen signs or shouted words, and some caption conventions use capitals for sound descriptions. In that case the practice belongs to non-speech information and is usually set by the project.
Brackets and sound descriptions
Square brackets or parentheses are commonly used to show sounds or to identify speakers who are off screen, such as a door closing or a name label. These are mostly a feature of captions for viewers who are deaf or hard of hearing, the difference explained in captions versus subtitles. Format differs by guide, but each project should pick one style and use it throughout.
Spacing and typographic details
- Leave no space before a comma, period, question mark or exclamation mark, except where the language’s own convention differs. Some languages place a space before certain marks, such as the colon or question mark in French.
- Use one space after a sentence, not two.
- Avoid ending a cue on a hanging comma or a dangling opening bracket.
- Keep marks consistent for the whole project: the same ellipsis style, the same dash style, the same quotation style.
Language and script variations
Punctuation is not the same worldwide. Quotation marks, the inverted question and exclamation marks of Spanish, and the periods of East Asian scripts all differ. In right-to-left scripts, punctuation at the end of a line can appear in the wrong place if the file or player is not set up for it, as discussed in right-to-left scripts. Following the rules of the target language is always better than copying the source.
Checking punctuation
Punctuation errors are among the most common slips in subtitles. Typical ones include missing end marks, inconsistent ellipses, wrong quotation marks and stray spaces. They are also easy to find with a careful read, which is part of subtitle proofreading, and many teams add them to a quality checklist. If you are unsure whether a mark helps, ask whether the viewer would miss it if it were gone. If not, leave it out.