Convert MP4 to Subtitles
Free Online Tool
Drop any MP4 video file and AudioSRT generates frame-accurate SRT or VTT subtitle files directly in your browser. Preview subtitles on the video before exporting. No upload, no account, no file size cap.
Convert MP4 to SRT Free →How MP4-to-subtitle conversion works
Upload your MP4
Drop your .mp4, .mov, or .webm file. AudioSRT extracts the audio track locally — your video is never sent to a server. Any resolution, any length.
Whisper transcribes the audio
OpenAI's Whisper model runs in a background Web Worker. The transcript builds progressively — each 30-second segment is available for editing as soon as it completes.
Style and export your subtitles
Preview subtitles burned onto your video in real time. Adjust font, size, stroke, shadow, and position. Export SRT, VTT, Premiere Pro JSON, or a fully-rendered MP4 with subtitles burned in.
What you get from an MP4-to-subtitle conversion
Live video preview
As you edit subtitle text or timing, the preview canvas updates instantly. Switch between 16:9 and 9:16 canvas sizes to check how subtitles sit in either aspect ratio.
Split lines by word
Click any word in the transcript to split a subtitle line at that exact point. Timestamps recalculate automatically — no manual time-code editing.
Four export formats
SRT, VTT, plain text, and native Adobe Premiere Pro JSON — all from one export menu. Import the JSON directly into Premiere's Text-Based Editing panel.
Entirely client-side
The MP4 never leaves your machine. All processing — audio extraction, transcription, subtitle rendering — happens inside your browser using Web Workers and WASM.
Convert your MP4 to subtitles now
Free to use. No signup. No upload. Works on any modern browser.
Open the Subtitle Converter →