SRT vs VTT vs TXT: Which Caption Format Your LMS Needs (Quick Guide)

SRT, VTT, and TXT files all turn spoken audio into readable text, but they serve different jobs in an LMS. Use SRT for simple, widely supported closed captions, VTT when you need web-first features like styling and chapter cues, and TXT when you only need a transcript with no timing. This guide explains the differences, what most LMS platforms accept, and how to keep timecodes and encoding clean.

Primary keyword: SRT vs VTT vs TXT

Key takeaways

• SRT is the most common caption file for LMS video players, with simple timing and broad compatibility.
• VTT (WebVTT) is ideal for web players and can support styling and extra cue types, but some LMS tools handle only basic VTT.
• TXT is a plain transcript (no timecodes) that works well for reading, studying, and search, but it won’t “sync” to video.
• Clean captions depend on consistent timecodes, correct formatting, and UTF-8 encoding.

What these file types are (in plain language)

Captions are text that shows on screen in sync with video, and transcripts are text you read separately. SRT and VTT are caption/subtitle formats because they include timecodes, while TXT is a transcript format because it usually does not.

In an LMS, the “right” format depends on what your video player accepts, what your accessibility plan requires, and how your learners use the content. Many courses use both: a timed caption file (SRT or VTT) plus a plain transcript (TXT or a formatted document).

SRT (SubRip Subtitle)

SRT is a simple text file with numbered caption blocks, start and end timecodes, and the caption text. It is widely used across video tools and is often the first format an LMS caption upload will accept.

• Timing: Yes (start and end time for each caption).
• Styling: Very limited; many players ignore styling even if you add it.
• Typical use in an LMS: Closed captions for recorded lectures and training videos.

VTT (WebVTT)

VTT is designed for the web and used by many HTML5 players. It looks similar to SRT but typically starts with a WEBVTT header and can support more advanced features like cue settings and some styling, depending on the player.

• Timing: Yes (like SRT).
• Styling: Better support than SRT in many web players, but results vary by platform.
• Typical use in an LMS: Captions for videos played in web-based players, especially when VTT is the default option.

TXT (plain text transcript)

TXT is just text, usually without timecodes. You can post it as a downloadable resource, paste it into an LMS page, or use it for studying and search.

• Timing: No (unless you manually add time markers, which still won’t behave like captions).
• Styling: Whatever your LMS text editor supports, since the file itself is plain text.
• Typical use in an LMS: Read-along transcripts, note-taking, and quick accessibility support when synced captions are not required.

SRT vs VTT vs TXT: key differences that matter in an LMS

When people ask “Which format does my LMS need?” they usually mean “Which file can I upload so captions work?” That decision comes down to timing support, styling needs, and what the platform’s player can actually render.

1) Timecodes and syncing

If you need text to appear at the right moment during playback, you need SRT or VTT. If you only need a reading copy, TXT is enough.

• SRT: Uses a simple start → end time range per caption.
• VTT: Uses a similar time range, but the format expects web-friendly conventions.
• TXT: No sync; learners read it separately.

2) Styling and formatting support

Most LMS caption uploads focus on readability and accessibility, not design, so styling often gets limited even when a format supports it. Still, VTT usually gives you more room than SRT when the player allows it.

• SRT: Typically plain text captions; some tools accept basic line breaks but ignore style tags.
• VTT: Can support cue settings (like position) and may support limited styling in compatible players.
• TXT: No built-in styling; presentation depends on where you paste or upload it.

3) Platform compatibility (what usually works)

Different LMS products bundle different video players, and those players decide what imports cleanly. In general, SRT and VTT are the most common caption upload options, and TXT is commonly accepted as a course resource.

• Safest “it usually works” caption file: SRT.
• Best for web video workflows: VTT.
• Best for a readable study aid: TXT.

If your LMS allows only one caption upload type, check its help docs for “closed captions,” “subtitles,” or “WebVTT.” You can also look at the upload dialog, which often lists accepted extensions like .srt or .vtt.

4) Search, reuse, and analytics

Captions (SRT/VTT) help learners follow the video and can support search in platforms that index timed text. Transcripts (TXT) are easier to reuse for handouts, study guides, summaries, and translations.

• Choose captions when you need on-screen support and better comprehension during playback.
• Choose transcripts when you need skimmable text for studying, quoting, or repurposing content.

Choose this if… (quick guide for LMS teams)

Use this section when you want the simplest decision with the fewest surprises.

Choose SRT if…

• Your LMS or video tool says it supports captions but does not mention WebVTT.
• You want maximum compatibility across players and editors.
• You do not need custom positioning, speaker labels on screen, or special cue types.

Choose VTT if…

• Your videos play in a modern web player and the platform explicitly supports .vtt.
• You want a web-native caption format for HTML5 workflows.
• You may need more control (and your player is known to respect it).

Choose TXT if…

• You need a transcript learners can download, print, or paste into notes.
• You do not need the text to display in sync with the video.
• You plan to repurpose the content into handouts, study guides, or translations.

Many course teams publish both: VTT/SRT for captions plus TXT for a full transcript. That pairing supports more learning styles and makes content easier to reuse later.

Practical tips: keep timecodes clean and avoid encoding issues

Most caption “errors” in an LMS come from small formatting problems. The good news is you can prevent most of them with a simple quality checklist.

Timecode hygiene checklist (SRT and VTT)

• Use consistent time format: SRT commonly uses commas for milliseconds (e.g., 00:01:02,500), while VTT commonly uses periods (e.g., 00:01:02.500); don’t mix them.
• Keep cues in order: Timecodes should increase from top to bottom with no backward jumps.
• Avoid overlaps: One caption should end before the next begins, unless your player explicitly supports overlaps.
• Leave tiny gaps when needed: If a player flickers between captions, a small gap can help readability.
• Keep line lengths readable: Break long lines into two lines so learners can read without rushing.
• Don’t “machine-gun” captions: Avoid very short durations for full sentences; give learners time to read.

Formatting pitfalls that break uploads

• Missing the VTT header: A VTT file should start with WEBVTT on the first line; some platforms reject files without it.
• Wrong arrow syntax: Time ranges should use the right separator (commonly -->) and spacing.
• Extra characters in timecodes: Copy-paste from spreadsheets can introduce hidden characters that make parsers fail.
• Bad cue numbering (SRT): Some players expect sequential numbers; duplicates can cause skipped captions.

Encoding and “weird character” fixes

If you see black diamonds with question marks, broken accents, or random symbols, you likely have an encoding issue. For most LMS workflows, UTF-8 is the safest default.

• Save as UTF-8: Use your text editor’s “Save with encoding” option and choose UTF-8.
• Watch for smart quotes: Some tools convert quotes and apostrophes into curly versions that may display poorly in older players.
• Keep line endings consistent: If a file works on one system but not another, try converting line endings (LF vs CRLF) in a code editor.
• Avoid BOM problems: Some platforms dislike a UTF-8 BOM at the start of a file; if uploads fail, re-save as “UTF-8 (no BOM)” if your editor offers it.

If you handle accessibility requirements, keep captions accurate and readable and make sure your LMS player can display them reliably. For general guidance on making video content accessible, the W3C Web Accessibility Initiative guidance for audio and video is a solid reference.

How to pick the right format for your specific LMS (step-by-step)

You do not need to guess. A short check in your LMS and video workflow will tell you what to deliver.

Step 1: Identify the player that actually shows the video

Your LMS might embed a separate video tool (or a third-party player) inside the course page. The player matters more than the LMS name.

• Open the video in the course.
• Find the captions menu (often “CC,” a gear icon, or “Subtitles”).
• Check whether it offers an upload option and what file types it lists.

Step 2: Decide whether you need captions, a transcript, or both

• Need on-screen text during playback: SRT or VTT.
• Need a reading copy for studying: TXT (or a formatted document built from the transcript).
• Need maximum support: Provide SRT/VTT + TXT.

Step 3: Match the format to your workflow

• Recording lectures weekly: Use the platform’s preferred caption upload type, then keep a TXT transcript for reuse.
• Publishing web-based modules: Favor VTT when supported, because it fits HTML5 players well.
• Sharing videos across many systems: Keep an SRT “master” and convert to VTT when needed.

Step 4: Run a quick QC test before course release

• Upload the file.
• Play the first 2 minutes and a middle section.
• Confirm the captions appear, stay in sync, and do not show strange characters.
• Check mobile playback if your learners use phones.

Common questions

1) Is VTT better than SRT?

VTT can be better in web-first players because it supports more features, but “better” only matters if your LMS player imports and displays those features. If you want the safest upload across tools, SRT often wins on compatibility.

2) Can I rename an SRT file to VTT (or vice versa)?

No, not reliably. The formats look similar, but timecode punctuation and headers differ, and a player may reject the file if the internal format does not match the extension.

3) Why do my captions drift out of sync over time?

Drift often comes from a mismatch between the caption timing and the video version (for example, a re-edited video) or from a frame rate/timebase difference introduced during export. Always confirm the caption file matches the exact video file uploaded to the LMS.

4) Do I need both captions and a transcript for accessibility?

Needs vary by organization and learner use cases. Captions support learners during playback, while transcripts support reading and review; providing both improves usability in many courses, especially for long lectures.

5) My LMS upload fails with “invalid file.” What should I check first?

Check the file extension, confirm the file is UTF-8, and validate basic formatting (VTT header, correct timecode syntax, and no hidden characters). Also confirm the LMS accepts that exact format for that video tool.

6) Should I use TXT with timestamps?

You can add timestamps to a TXT transcript for navigation, but it still will not behave like captions in most players. If you want clickable or synced text, use SRT or VTT and then export a separate TXT transcript for reading.

7) What’s the difference between subtitles and captions in an LMS?

People often use the terms interchangeably. In many course tools, “captions” usually means on-screen text that includes spoken dialogue and key audio info, while “subtitles” may focus on dialogue only or on translation, depending on the context.

When you might want help converting or cleaning files

If you manage many courses, small caption issues can create big support work. Consider getting help when you need consistent formatting across many instructors, multiple languages, or strict QC for timecode and encoding issues.

• High volume: Weekly lecture uploads across several departments.
• Multiple outputs: You need SRT and VTT, plus a TXT transcript for learners.
• Messy audio: Heavy accents, crosstalk, or technical terms that need careful review.
• Existing captions need a polish: You have a rough file that needs fixing.

If you already have a draft caption file and only need cleanup, transcription proofreading services can help you correct text, formatting, and consistency without starting from zero.

If you need on-screen text files for course videos, closed caption services can deliver caption-ready outputs in common formats such as SRT and VTT, along with readable transcripts when needed.

When you want a dependable workflow for LMS-ready captions and transcripts, GoTranscript can help you choose the right format and deliver files that upload cleanly. You can start with GoTranscript’s professional transcription services for transcripts, captions, and related classroom-ready text outputs.