Auto Subtitle Generator
Generate subtitles from audio or video with AI — accurate timed captions in 9+ languages, edit each line, then download as SRT or VTT. Free, no signup.
About the Auto Subtitle Generator
This free auto subtitle generator turns any audio or video file into timed captions in about a minute. Upload an MP3, WAV, M4A, MP4 or WebM file up to 25 MB, pick the spoken language (or leave auto-detect on), and AI speech recognition transcribes it into subtitle lines with precise start and end timestamps. For video files, the audio track is what gets transcribed.
Every line is editable right on the page — click any subtitle to fix a name, a technical term or punctuation before exporting. When you're happy, download the result as SRT (the universal format accepted by YouTube, Premiere Pro, DaVinci Resolve, VLC and virtually every player) or WebVTT (the web-native format for HTML5 video and most embedded players). You can also copy the full plain-text transcript for show notes, blog posts or translations.
Language support covers English, Urdu, Hindi, Arabic, Spanish, French, German, Chinese and Japanese, with auto-detection for everything else the model knows. The 25 MB limit corresponds to roughly 25 minutes of compressed audio — for longer videos, extract the audio track first (an MP3 of a 30-minute video is far smaller than the video itself) and upload that instead.
How to Use the Auto Subtitle Generator
- 1Upload an audio or video file (up to 25 MB — about 25 minutes of audio).
- 2Choose the spoken language, or leave it on auto-detect.
- 3Click Generate Subtitles and wait while the AI transcribes.
- 4Edit any lines that need fixing, then download as SRT or VTT, or copy the transcript.
Frequently Asked Questions
What's the difference between SRT and VTT subtitles?
SRT is the older, universal format: numbered blocks with comma-separated milliseconds (00:01:23,456), accepted by YouTube, editing suites and desktop players everywhere. WebVTT is the web standard: it starts with a WEBVTT header, uses dots for milliseconds and supports styling and positioning, and it's what HTML5 <track> elements and most embedded web players require. This tool exports both from the same transcription, so grab whichever your platform needs — or both.
How accurate is AI subtitle generation?
For clear speech in major languages, modern speech recognition typically lands in the 90–95%+ range — usually a handful of fixes per minute of audio rather than a rewrite. Accuracy drops with heavy background music, crosstalk, strong accents and niche jargon. That's why every line here is editable before export: proper nouns and technical terms are the usual suspects worth a quick pass.
Why is there a 25 MB file limit?
25 MB is the transcription service's per-file cap, which fits roughly 25 minutes of compressed audio (a 128 kbps MP3). Video hits the cap much sooner because the picture dominates file size — so for anything longer than a few minutes of video, extract the audio track to MP3 or M4A first and upload that. The subtitles you get back work with the original video, since the timing is identical.
Does it work with video files or only audio?
Both. For video files (MP4, WebM, MOV and other common containers) the audio track is extracted and transcribed — the picture itself isn't analysed. The resulting SRT or VTT file lines up with the video's timeline, ready to upload alongside the video on YouTube or import into your editor.
Which languages are supported?
The language picker offers English, Urdu, Hindi, Arabic, Spanish, French, German, Chinese and Japanese, and auto-detect handles dozens more — the underlying model was trained on a very wide range of languages. Selecting the actual language instead of auto-detect can improve accuracy, especially for short clips where detection has little audio to work with.
Are my files stored anywhere?
No. Your file is sent over an encrypted connection to the transcription service, processed, and the text is returned — it isn't kept afterwards, and the subtitles only exist in your browser until you download them. Refreshing the page discards everything.