opnai / Subtitle Generator
Subtitle Generator
Long files can take a few minutes. You can leave this page: if you come back in this browser within 24 hours, we reconnect to your job. Files are deleted automatically after 24 hours and we do not log or train on your content.
Create subtitle files with timestamps from a video or audio recording. Choose SRT, which most editors and video sites accept, or WebVTT for use on web pages, and download the file when it is ready.
The tool listens to the speech, splits it into timed captions and returns the file along with a preview of the first lines so you can judge it quickly. Your upload is deleted automatically after 24 hours.
How to use Subtitle Generator
- Drop a video or audio file onto the box or choose it from your device. Files up to 100 MB and 30 minutes are accepted.
- Choose the spoken language or keep Auto-detect, and pick SRT or WebVTT as the subtitle format.
- Press Generate subtitles and follow the upload and processing progress.
- Check the preview, then download the subtitle file and load it in your video player or editor. Press Delete now to remove your upload at once.
Features
Choose the format your player, editor or website expects. Plain text is also available.
Each caption has start and end times so it lines up with the speech.
The first lines are shown on the page so you can spot problems early.
Upload a video directly or just its audio track.
No content logging, no training on uploads, automatic deletion after 24 hours.
Using the file
Most video players load an SRT automatically if it has the same name as the video, and editing programs can import it as a caption track. On the web, add a VTT file with a track element or upload it to your video platform.
Always read through the captions before publishing. Names, numbers and technical words are the most likely mistakes, and readers who depend on captions deserve accurate ones.
Tips for better captions
Clean audio produces cleaner captions. If the video has loud background music, use the original voice track when you can. Splitting very long videos into parts also makes review easier.
Frequently asked questions
How accurate is the transcript?
On clear speech from a single speaker in a quiet room the result is usually very good. Accuracy drops with strong accents, overlapping voices, background noise, music, poor microphones and specialist vocabulary. Names, numbers and technical terms are the most common mistakes, so read the transcript before you publish or rely on it.
What is the difference between SRT and VTT?
Both are plain-text subtitle formats. SRT is the most widely supported by editors and video sites. WebVTT is the standard for the HTML video element and web players.
What are the file limits?
Up to 100 MB and up to 30 minutes of audio or video per file. Longer recordings should be split into parts first. The page checks the length in your browser before uploading so you do not wait for a file that would be rejected.
Is my recording private?
Your file is used only to produce the transcript. We do not log what is said, we do not train models on uploads, and the file and result are deleted automatically after 24 hours. You can remove them sooner with the Delete now button.
Will the timing be perfect?
Timing is usually close but not frame-exact. Captions may start a little early or late, especially around pauses, music or overlapping speakers. Review and adjust in a subtitle editor if you need precision.
Can it translate the subtitles?
No. Subtitles are written in the language that is spoken in the recording.