SRT

Overview

SRT (SubRip Text) is a widely used subtitle file format composed of sequentially numbered cues, each containing a start and end time and one or more lines of text. Its simplicity, human-readable syntax, and broad tool support make it a staple for festival screeners, indie deliverables, and user-generated captions. Because it lacks styling beyond basic line breaks and italics, SRT is best for workflows prioritizing compatibility over rich formatting.

Structure and Syntax

An SRT cue comprises: (1) an integer index, (2) a timecode range in HH:MM:SS,mmm --> HH:MM:SS,mmm, and (3) one or more text lines, followed by a blank line. The comma for milliseconds and the arrow token must be exact; malformed punctuation leads to importer errors. While SRT supports rudimentary markup (e.g., {\i1} in some tools), reliance on non-standard tags reduces portability. For accessibility, keep line length under ~42 characters per line and limit to two lines per cue.

Production and Localization

Editors export reference SRTs from NLEs or speech-to-text tools, then translators produce language variants while preserving timecodes. Quality control includes reading speed (characters per second), shot change alignment, and consistency of speaker IDs or sound effect conventions (e.g., [sighs], ♪ for lyrics). Because SRT lacks positional data, critical placement (e.g., avoiding burned-in chyron clashes) must be handled by the player or upgraded to a richer format during mastering.

Delivery and Pitfalls

Streaming platforms may transcode SRT to internal formats; test for encoding issues (UTF-8 vs Windows-1252), right-to-left scripts, and emoji fallback. Avoid three-line cues, stacked italics, or hard line breaks that produce mid-word wraps on small screens. Maintain version control—dialogue edits ripple through all language files; a central glossary and termbase prevent drift across episodes.

Related Terms

• VTT, TTML/IMSC, closed captions (CC), SDH.