SRT vs SSA
A detailed comparison of SubRip Subtitle and SubStation Alpha — file size, quality, compatibility, and which format to choose for your workflow.
SubRip Subtitle
Documents & TextSRT is the most widely used subtitle format with simple timestamps and text.
About SRT filesSubStation Alpha
Documents & TextSSA (SubStation Alpha) is a subtitle format with styling and positioning.
About SSA filesStrengths Comparison
SRT Strengths
- Trivially simple — every video player reads SRT sidecar files automatically.
- Plain text — editable in Notepad, grep-able, diff-friendly.
- Universal tooling — OCR, translation, and timing apps all speak SRT natively.
- Tiny file sizes — a 2-hour movie of subtitles is usually under 100 KB.
SSA Strengths
- Plain text format — editable in Notepad.
- Rich styling compared to SRT (named styles, per-character formatting).
- Universal desktop player support since the 2000s.
- Forward-compatible — modern players open SSA as ASS.
Limitations
SRT Limitations
- No formal standard — edge cases (nested tags, encoding, line count) vary.
- No styling beyond basic HTML — no positioning, no colors beyond italic/bold.
- Character encoding ambiguity — some SRTs are Windows-1252, some UTF-8, some UTF-16.
- Cannot represent multiple speakers, sound effects, or precise positioning like SSA/ASS can.
SSA Limitations
- Superseded by ASS for new content.
- Not supported in HTML5 <video>.
- Commercial streaming services ignore SSA.
- Multiple implementations disagree on edge cases.
Technical Specifications
| Specification | SRT | SSA |
|---|---|---|
| MIME type | application/x-subrip | text/x-ssa |
| Extension | .srt | .ssa |
| Structure | Numbered blocks: index → timecodes → text → blank line | — |
| Timecode format | HH:MM:SS,mmm --> HH:MM:SS,mmm | — |
| Encoding | Typically UTF-8 (modern) or CP1252 (legacy) | — |
| Successor | — | .ass (Advanced SubStation Alpha) |
| Timecode precision | — | Centisecond (0.01s) |
| Authoring | — | Aegisub |
Typical File Sizes
SRT
- 1-hour TV episode (English) 30-80 KB
- 2-hour movie (English) 50-120 KB
- Anime episode with stylized Japanese 80-200 KB
SSA
- TV episode dialogue 30-90 KB
- Anime episode with signs and songs 80-200 KB
Ready to convert?
Convert between SRT and SSA online, free, and without installing anything. Encrypted upload, automatic deletion after 2 hours.
Frequently Asked Questions
SRT (SubRip Subtitle) is a document format used to store paginated text, with optional formatting, tables, images, hyperlinks, headers and footers. It sits in the documents & text family and is typically associated with a specific office suite or publishing pipeline that defined the format and ships the canonical reader.
SSA (SubStation Alpha) is a document format used to store paginated text, with optional formatting, tables, images, hyperlinks, headers and footers. It sits in the documents & text family and is typically associated with a specific office suite or publishing pipeline that defined the format and ships the canonical reader.
Modern office suites — Microsoft Word, Google Docs, LibreOffice Writer, Apple Pages — open most SRT files with reasonable fidelity. If your installed software does not support SRT, convert to DOCX or PDF first using KaijuConverter; both open in virtually every reader, including free online viewers.
Modern office suites — Microsoft Word, Google Docs, LibreOffice Writer, Apple Pages — open most SSA files with reasonable fidelity. If your installed software does not support SSA, convert to DOCX or PDF first using KaijuConverter; both open in virtually every reader, including free online viewers.
Upload the SRT to KaijuConverter and pick DOCX, PDF, ODT, RTF, HTML, Markdown, or plain text. Our pipeline runs LibreOffice headlessly plus pandoc for text formats — the same engines behind professional document pipelines. Styles, tables, images, and hyperlinks survive the conversion intact.
Yes, to a high degree. Standard fonts, headings, lists, tables, images, hyperlinks and page structure transfer cleanly. Custom fonts substitute to the closest match if not embedded; obscure layout features unique to SRT (frames, legacy macros) may flatten to static content in the target format.