SRT files
Make an SRT file from any video, free.
Word-level timing, fully editable text, unlimited free downloads — and your video is never uploaded to make one.
An SRT file is a plain-text subtitle file listing numbered cues, each with a start and end timestamp and the text shown between them. LumaCaption generates one from your video’s audio with word-level timing, lets you edit the text before you download, and never uploads the video file itself.
An SRT is the most portable thing in video: a text file with numbered cues, a start and end time for each, and the words in between. YouTube takes it, LinkedIn takes it, Vimeo takes it, VLC reads it, and every professional editor imports it. It has no styling and no positioning, which is exactly why it works everywhere.
What separates a good SRT from a bad one is not the format — it is the timing and the spelling. Cues generated on a fixed interval drift out of step with speech; cues generated from real word timings do not. And a subtitle file with your product name spelled three different ways is worse than no subtitle file at all, because you uploaded it and moved on.
Timed to actual speech
Cue boundaries come from word-level timings taken from your audio, not from a fixed interval — so a pause is a gap, not a cue that runs long.
Edit before you download
Click any word to fix a spelling, a name or a piece of jargon. The timing stays attached to the word you corrected.
Free and unlimited
SRT, WebVTT and plain-text downloads are unlimited on every plan including free. Nothing about a subtitle file is behind a paywall.
No video upload
The file never leaves your device — only the audio is used to work out the words. Unreleased and client footage included.
What an SRT file actually contains
The format is small enough to describe completely. Each cue is four parts: a 1-based index on its own line, a timing line with the start and end separated by a space-arrow-space, the caption text on one or more lines, then a blank line before the next cue.
Timestamps are `HH:MM:SS,mmm` — hours, minutes, seconds, and milliseconds after a **comma**. The comma is not a typo and it is the single most common thing people get wrong when hand-editing: WebVTT uses a period in the same position, and a period in an SRT makes the cue unparseable in strict players.
- Index
- A 1-based counter on its own line. Some players tolerate gaps and duplicates; do not rely on that.
- Timing line
- `00:00:04,120 --> 00:00:06,480`. Comma before the milliseconds, exactly one space each side of the arrow.
- Text
- One or two lines. No styling and no positioning — anything you want styled has to be burned into the picture instead.
- Blank line
- Separates cues. A missing blank line merges two cues into one and is the second most common hand-editing failure.
Where an SRT is the right output — and where it is not
Use an SRT when the destination reads subtitle files: YouTube indexes them for search and can auto-translate them, LinkedIn attaches one through the composer, Vimeo and most CMS video players accept them, and every editor from Premiere to DaVinci imports them for further work.
Do not use one when the look matters. SRT carries no font, no colour, no position and no motion — a styled, word-by-word, animated caption cannot be expressed in the format at all. That output has to be burned into the picture, and the two are not alternatives so much as different products from the same edit. Most people who need both simply take both, since the export and the download come from the same corrected transcript.
What you can download, on every plan
| Format | Extension | Carries | Typical destination |
|---|---|---|---|
| SubRip | .srt | Numbered cues, start/end times, plain text | YouTube, LinkedIn, Vimeo, editors |
| WebVTT | .vtt | Same, plus a WEBVTT header and markup escaping | HTML5 <track>, web players |
| Transcript | .txt | The words, no timings | Show notes, blog posts, translation briefs |
| Burned-in video | .mp4 | Styling, colour, position, motion | Reels, Shorts, TikTok, Status |
Subtitle downloads are unlimited on every plan, including free. Exports are free and unlimited too — transcription minutes are the only thing metered.
How it works
Add your video
Any common format. The file is never uploaded — only the audio is used to work out the words and their timings.
Correct the text
Fix names, products and jargon by clicking the word. Timings stay attached to what you corrected.
Download the SRT
Free and unlimited, on every plan. Take the VTT and the plain-text transcript at the same time if you need them.
Common questions
What is an SRT file?
A plain-text subtitle file. Each cue is a 1-based index, a timing line in the form `00:00:04,120 --> 00:00:06,480`, the caption text, and a blank line. It carries no font, colour or position, which is exactly why every platform and editor accepts it.
Is the SRT download free?
Yes, unlimited, on every plan including free. Transcription minutes are the only metered thing here — subtitle downloads and video exports are not.
Why does my SRT use commas in the timestamps?
Because the SubRip format specifies a comma before the milliseconds — `00:00:04,120`. WebVTT uses a period in the same position. Swapping them is the most common hand-editing mistake and makes cues unparseable in strict players, so if you edit an SRT by hand, leave the commas alone.
Can an SRT contain styled or animated captions?
No. The format has no font, colour, position or motion. Anything styled has to be burned into the video picture instead. Both come out of the same edit here, so it is normal to take the SRT for the platform that reads files and the burned-in export for the platforms where the look is the point.
Do I need to upload my video to get an SRT?
Not here. The video file stays on your device — only the audio is used to find the words. For footage under NDA or not yet published, that is usually what decides which tool gets used.
