SRT or VTT: which one do you need?
SRT (SubRip) is the most widely supported subtitle format. Each cue has a number, a timing line such as 00:01:02,500 --> 00:01:05,000 and one or two lines of text. YouTube, Premiere Pro, DaVinci Resolve, Final Cut, VLC and many smart TVs read it.
WebVTT is the format browsers use for the HTML <track> element, so web players and many hosting platforms expect it. It starts with a WEBVTT header, uses a dot before the milliseconds and can carry cue positions and comments. Converting from VTT to SRT drops those extras; converting from SRT to VTT keeps italics, bold and underline and safely escapes characters like & and < that would otherwise break the file.
Need just the words, for show notes, a blog post or a script review? Choose TXT to get a clean transcript with the tags and timings removed, or turn on timestamps for a quick reference copy.
Three kinds of out-of-sync subtitles, three fixes
Before you start shifting, watch where the subtitles go wrong. The pattern tells you which fix to use:
- Always off by the same amount, every line is, say, two seconds early. Use Shift everything and move the cues later (or earlier if they appear late). If you know exactly when one line should appear, type that time instead and the offset is worked out for you.
- Fine at first, wrong after a certain point, typical after an ad break was cut or a scene was trimmed. Click the first cue that's off and shift from that cue onward.
- Fine at the start, steadily worse towards the end, the subtitles were made for a different cut or frame rate. Use Sync to two points: type when an early cue and a late cue should really appear, and every cue in between is stretched to match.
Two-point sync also tells you when the stretch matches a known frame-rate change, which is a strong hint the file was made for a different release of the video.
Frame rates: why 23.976 and 25 fps subtitles drift
Films are usually shot at 23.976 or 24 frames per second, while European broadcast versions run at 25 fps, the same frames played about 4% faster. Subtitles timed for one version start in sync on the other and then slip by about two and a half minutes for every hour of running time.
Pick what the subtitles were made for and what your video plays at, or tap one of the common pairs. Every timestamp is multiplied by the exact ratio (NTSC rates like 23.976 are calculated as 24000/1001, not rounded), so the drift disappears. Not sure about your video's frame rate? The video info tool shows it.
Tidy subtitles are easier to read
The checks panel looks for the problems that make subtitles flicker, get rejected by platforms or vanish before anyone can read them: cues that overlap the next one, cues out of time order, cues that end before they start, empty cues, lines that are too long and cues shown for too short a time to read (more than 20 characters per second). Each problem has a one-click fix, and the affected cues are highlighted in the list.
A common guideline is to keep lines to about 42 characters and cues to two lines. Re-wrap reflows long cues into balanced lines without breaking dialogue lines that start with a dash. Made a change you don't like? Press Undo (or Ctrl+Z) to step back through every edit.
Starting from scratch? The auto subtitle generator transcribes speech on your device and exports SRT you can polish here. For a talk you're about to record, plan its length with the script timer.