SMI to TXT Subtitle Converter
Transform Synchronized Accessible Media Interchange subtitles into TXT format, extracting a clean plain-text transcript instantly and privately in your browser.
Drag & drop your SMI file here
or click to browse
Supports .smi, .sami, .html files up to 50 MB
Free Online SMI to TXT Converter
Our SMI to TXT converter reads Synchronized Accessible Media Interchange input and produces Plain Text output entirely in your browser. All timing and styling are stripped so you are left with a clean text transcript. The conversion runs client-side, so your subtitle files are never uploaded to a server.
SMI to TXT Code Syntax & Structure Inspection
Side-by-side code inspection illustrating header definitions, timestamp syntax, and cue payload formatting
SMI vs TXT Technical Specifications
SMI
SMI (SAMI, Synchronized Accessible Media Interchange) is a Microsoft subtitle format built from HTML-like <SYNC> elements whose Start attribute is given in milliseconds. SMI supports multiple language tracks through CSS classes and was widely used for Windows Media Player captions and accessibility content.
TXT
TXT (Plain Text) output strips away all timing, sequence numbers, and formatting, leaving subtitle text as a clean transcript. This is useful for extracting scripts, building searchable transcripts, feeding text into translation or AI tools, or repurposing subtitle content as plain documents.
Format Differences
Conversion Troubleshooting & Gotchas
Practical solutions for player compatibility, character encoding, and timing synchronization
Subtitle timing drifts or appears out of sync on media players
Video files frequently differ in framerate (e.g., 23.976 fps vs 25 fps). If the timing drifts steadily, use our Subtitle Sync tool to adjust the global offset or framerate stretch.
Characters appear as garbled symbols or question marks (Mojibake)
Legacy files saved in Windows-1252, Shift-JIS, or GBK may render incorrectly. Our exporter standardizes output to clean UTF-8. Use our Subtitle Encoding Converter if the source file is corrupted.
Overlapping captions when multiple speakers talk simultaneously
Different formats handle overlapping dialogue differently. If your target player cannot render stacked cues cleanly, open the file in our Subtitle Editor to adjust individual cue timings.
Video editing software (Premiere, DaVinci, Final Cut) rejects the file
Professional NLE software enforces strict syntax rules. Our converter eliminates malformed line breaks and non-standard tags, producing clean, standardized files.
Features
Why Convert?
Common Use Cases
Transcript Extraction
Pull a clean plain-text transcript from subtitles for notes, scripts, or documentation.
Search & Indexing
Index subtitle content as searchable text without timing noise.
AI & Translation Input
Feed clean text into translation tools, summarizers, or other AI workflows.
Related Formats
How It Works
- 1
Upload your .smi file by dragging it in or browsing.
- 2
The parser reads the Synchronized Accessible Media Interchange structure and extracts each cue's start, end, and text.
- 3
TXT output has no timestamp structure.
- 4
Timing and formatting are removed, leaving only the dialogue text.
- 5
The output .txt file is generated and ready to download.
More Subtitle Tools
Frequently Asked Questions
It reads a Synchronized Accessible Media Interchange file, parses each cue's timing and text, removes timing and formatting for Plain Text, and writes a valid .txt file.
Absolutely. Every conversion runs client-side in your browser. No subtitle data, file contents, or metadata is ever transmitted to a server.
Yes. SMI timing, styling, and markup are removed. Cue text is retained and separated by newlines; existing multi-line cues keep their internal line breaks.
Yes, completely free with no sign-up, no watermarks, and files up to 50 MB each. All processing happens in your browser, so your files are never uploaded to a server.
Timestamps are removed because TXT has no timestamp structure.
Yes. The converter is fully responsive and works in any modern mobile browser on iOS and Android.
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