What Is an SRT File? (And How It Differs from VTT)

SRT comes from SubRip, an old Windows program that pulled subtitles off DVDs. The format stuck because it is so simple: anyone can read and edit it by hand, and nearly every player, video editor and video platform accepts it.

What is an SRT file?

Here is a complete, valid SRT file with two subtitles (called cues):

1
00:00:01,000 --> 00:00:04,000
Where were you last night?

2
00:00:04,500 --> 00:00:07,250
I was at the station.
<i>Waiting for you.</i>

• Index (1, 2): the cue number, counting up from 1.
• Timecode line (00:00:01,000 --> 00:00:04,000): start and end time as hours:minutes:seconds,milliseconds. SRT uses a comma before the milliseconds, and the arrow is two hyphens and a greater-than sign with a space on each side.
• Text: one or two lines of dialogue. Many players also understand simple tags such as <i> for italics and <b> for bold.
• Blank line: ends the cue. A missing blank line is a common reason a player merges two subtitles or stops reading the file.

That's the whole format. An SRT file holds no video, no fonts and no colours. It is just text and times, which is why it's tiny and easy to fix. (Spanish speakers call it an archivo SRT; it's the same file.)

What is a VTT (WebVTT) file?

WebVTT (Web Video Text Tracks) is the subtitle format of the web: it is what the HTML5 <track> element loads, and many online video platforms and course sites accept it. YouTube accepts both .srt and .vtt uploads. The same two cues in VTT:

WEBVTT

NOTE Optional comment

1
00:00:01.000 --> 00:00:04.000
Where were you last night?

00:00:04.500 --> 00:00:07.250 line:10% align:center
I was at the station.

• WEBVTT header: the file must start with WEBVTT. Without it, browsers reject the file.
• Period before milliseconds: 00:00:01.000, not a comma. The hours can be left out (00:01.000).
• Cue numbers are optional: the second cue above has none.
• Cue settings after the times, such as line:10% align:center, move or align the text, e.g. to the top of the frame.
• Extras: NOTE comments, STYLE blocks, and voice tags like <v Anna> to mark the speaker.

SRT vs VTT (and where ASS fits)

Rule of thumb: use SRT for desktop players, TVs and video editors, VTT for a website or web player, and ASS only when you need styled or positioned text, typically made in Aegisub.

How to open an SRT file

To read or check the text

It's plain text. On Windows, right-click → Open with → Notepad. On a Mac, right-click → Open With → TextEdit. Don't open it in Word, which can change line breaks and encoding if you save.

To watch it with the video

• Drag and drop: start the video in VLC and drag the .srt onto the window.
• Menu: in VLC, Subtitle → Add Subtitle File.
• Same name: put movie.mp4 and movie.srt in the same folder. VLC and most other players load it automatically.

The same tricks work for .vtt in VLC. In a browser, VTT is loaded by the page's video player, not opened directly.

How to create or edit an SRT file

Typing timecodes by hand is fine for a few lines. For a whole video, use a subtitle editor: Subtitle Edit (free, Windows) lets you set start and end times while the video plays and catches overlaps. Already have the script as text? The TXT to SRT tool turns each line into a cue with placeholder timing for you to adjust.

How to convert between SRT, VTT and text

All of these run in your browser, free, with no signup:

• SRT to VTT: adds the WEBVTT header and switches commas to periods, for web players.
• VTT to SRT: for desktop players and video editors.
• SRT to TXT: strips numbers and timecodes, leaving just the dialogue.
• TXT to SRT: turns a script into a subtitle file.
• Subtitle converter: all of the above on one page.

Common SRT problems and fixes

• Garbled characters (é instead of é, or boxes and question marks): an encoding mismatch. Open the file in an editor that lets you choose the encoding (Notepad++: Encoding menu), find the one where the text reads correctly, then convert and save as UTF-8.
• Subtitles out of sync by the same amount throughout: shift the whole file with the shift subtitles tool. If the drift grows over the film, the file was made for a different frame rate; fix it with the subtitle FPS converter.
• Lines too long, or one long line with a stray word underneath after importing into an editor: split them into two balanced lines with the subtitle line breaker.
• Player ignores the file: check the extension is really .srt (not .srt.txt), the timecodes use commas, and every cue ends with a blank line. A .vtt without the WEBVTT header fails the same way.

How to translate an SRT or VTT file

Pasting a subtitle file into a general translator tends to damage the timecodes, because the translator treats them as text. A subtitle translator reads the cues, translates only the dialogue, and gives the file back with the same numbering and timing. Use the SRT translator or the VTT translator. The first 30 lines are free to preview, and you can export the translation alone or as bilingual subtitles.

Frequently asked questions