Convert MP4 to SRT.
Generate accurate SRT subtitles from an MP4 video automatically with Whisper AI — perfectly timed caption cues.
Why add SRT subtitles to your video
SRT (SubRip) is the most widely-supported subtitle format — a simple text file of numbered cues, each with a start/end timecode and a line or two of text. Adding it to a video pays off three ways: accessibility (deaf and hard-of-hearing viewers), reach(a large share of social video is watched with the sound off, so on-screen captions keep people watching), and discoverability (the text is searchable and gives platforms something to index). Auto-generating the SRT means you skip the tedious part.
How the transcription works
FileWhirl pulls the audio from your MP4 and runs it through Whisper (the faster-whisper build, small model) with voice-activity detection, which trims silence so the cue timings line up cleanly with speech. It handles a wide range of accents well. As with any automatic transcription, it's worth a quick read-through to fix proper nouns, brand names and technical jargon before you publish.
Use it on the web or go further
SRT works in most players and on YouTube. For an HTML5 <video> on your own site you'll want WebVTT instead — convert it with SRT to VTT. Or open the transcript in TranscriptAI to turn it into notes, a summary or action items.
How it works
- 01
Upload your MP4
Drop a file or pick one from your device. Private by default.
- 02
Transcribe with Whisper
faster-whisper (small model + voice activity detection) produces an accurate transcript — no paid API in the loop.
- 03
Open in TranscriptAI
Grab your SRT, or open it in TranscriptAI for notes, summaries, flashcards and action items.
Accurate Whisper AI transcription
Voice activity detection for clean output
Private uploads, auto-deleted after 1 hour
No watermark, no signup to try
Free and open-source engine (Whisper)
Unlock notes & summaries in TranscriptAI
Your file is ready. Want to do more with it?
Open this file in TranscriptAI to generate a transcript, summary, structured notes, flashcards, quiz questions or action items — automatically.
Common questions
Is it free?+
Yes — convert MP4 to SRT free. No signup, no watermark, no daily cap.
Is my recording private?+
Uploads go to a private bucket, are transcribed, and auto-delete after 1 hour. Files never touch a third-party API.
How accurate is it?+
We use Whisper's small model with voice activity detection — strong accuracy across accents, and clean handling of pauses and silence.
Related conversions