Subtitles out of sync, or in the wrong format for your player or website? Fix both here.
What it does
- Convert SRT ↔ WebVTT (
.vtt), or to a plain-text transcript with the timings removed. - Shift every cue earlier or later by any number of seconds.
- Stretch timings to fix subtitles that start in sync but drift further off as the video plays.
Open a .srt or .vtt file, or paste the contents. The output updates live.
Fixing subtitles that are out of sync
Constant offset — every line is early or late by the same amount:
- Find a line where you can hear the speech start, and note how far off the subtitle is.
- Enter that in Shift timing: positive if subtitles appear too early, negative if too late (e.g.
-1.5).
Growing drift — fine at the start, seconds off by the end. This is almost always a frame-rate mismatch between the subtitle source and your video:
| Subtitle made for | Your video is | Stretch value |
|---|---|---|
| 25 fps (PAL) | 23.976 fps | 1.0427 |
| 23.976 fps | 25 fps (PAL) | 0.959 |
| 24 fps | 23.976 fps | 1.001 |
If there's drift and an offset, set the stretch first, then shift.
SRT vs VTT
- SRT is the universal format for video players (VLC, MPC, Plex, most TVs) and YouTube uploads.
- WebVTT is what HTML5
<video>on websites requires, and supports styling.
The differences are small — VTT uses a WEBVTT header and . instead of , before milliseconds — but players are strict about them.
Don't have subtitles at all?
Subtitle Studio AI generates subtitles from any video or audio using offline speech recognition (faster-whisper), with word-level timing, an editable cue table, styling presets, and export to SRT, VTT, TXT or ASS — or burn them into the video. Whispering Notes AI is the transcription-first version for meetings, lectures and interviews.
More audio, speech & subtitles
- Audio ConverterConvert audio files to MP3 or WAV, change bitrate and sample rate, downmix to mono, or extract the soundtrack from an MP4 video. Batch-friendly and nothing is uploaded.
- Text to Speech OnlinePaste any text and hear it read aloud with your device's voices. Adjust speed and pitch, follow along with word highlighting. Free, no sign-up, nothing sent to a server.
- Base64 Encoder & DecoderEncode text to Base64 or decode Base64 back to text, right in your browser. Handles emoji and accented characters correctly, with URL-safe output.
- HTML Entity Encoder & DecoderEscape HTML so tags display as text, or decode entities back into characters. Supports all HTML5 named entities, in your browser.
Try these next
- Guess the Language
- Guess the Currency
- Tic Tac Toe
- Random Name Generator
- Remove EXIF Data & GPS Location from Photos
- Barcode Generator — Code 128, EAN-13, UPC & More
- Fortune Generator
- Pet Name Generator
- Random Color Palette Generator — Free, Copy Hex Codes
- What Element Are You? (Earth, Fire, Air, Water)
- Morning, Afternoon, or Night Person? Quiz