Drop an MP4 and download a WebVTT file timed to what is said in it. Put the two side by side on your server, add one line of HTML, and the browser shows a CC button.
How it works
Drop the file into the box, or paste a direct link to it if it is already on your server or in cloud storage.
Correct names and terms on the transcript page. The corrections go into every file you download.
Save it next to the video with a clear name such as lesson-1.en.vtt.
Using the file
With lesson-1.mp4 and lesson-1.en.vtt in the same folder on your site:
<video controls src="lesson-1.mp4"><track kind="captions" src="lesson-1.en.vtt" srclang="en" label="English" default></video>
Three things go wrong often enough to mention:
crossorigin. Hosting both files together avoids it..vtt should be served as text/vtt. Most hosts do this already.file://. Test on a local web server.More on players and several languages: subtitles for HTML5 video.
If you only have big files
A 4K MP4 of a one-hour lesson can be several gigabytes; its audio is about 50 MB. The free extract audio from video tool pulls the audio out in your browser, and a VTT made from that audio fits the video exactly because the timeline is the same. Files up to 5 GB or 10 hours are accepted either way.
Need SRT for an editor as well? It comes from the same upload: MP4 to SRT.
Sample output
WEBVTT 00:00:34.680 --> 00:00:46.500 fourscore and seven years ago our fathers brought forth upon this continent a new nation conceived in in liberty, and dedicated to the proposition 00:00:46.500 --> 00:00:50.300 that all men are created equal. 00:00:50.300 --> 00:00:57.500 Now we are engaged in a great civil war, testing whether that nation, or any nation so conceived 00:00:57.500 --> 00:01:01.620 and so dedicated, can long endure. 00:01:01.620 --> 00:01:07.920 We are met on a great battlefield of that war we have come to dedicate a portion of that field 00:01:07.920 --> 00:01:14.240 as a final resting place for those who here gave their lives that their nation might live 00:01:15.360 --> 00:01:18.800 it is altogether fitting and proper that we should do this
Real output, unedited: a public-domain LibriVox reading of the Gettysburg Address (2 min 41 s) transcribed here in October 2026. The repeated word and the missing capitals are what came back; you would fix those on the transcript before downloading.
Before you rely on it
Each cue is a phrase from the transcript with its start and end time. Most run a few seconds. A passage spoken without a pause can come out as one long cue of up to about half a minute, so split those in your editor if your platform wants two short lines at a time.
Cue times are taken from the recording itself, so the file lines up with the video or audio you uploaded. If you trim the start of the video afterwards, shift the cues by the same amount in your editor.
On public test recordings, about 7 words in 100 differed from the reference for clean English read speech, between 4 and 9 in 100 for Spanish, Portuguese, Russian, French and German, and about 21 in 100 for Hindi. Noisy rooms, music and crosstalk do worse. Method and every number: the benchmark.
Open the transcript, correct a misheard name or number on its line, and the SRT and VTT you download carry the correction with the timing unchanged.
You get the subtitle file. Fonts, colours, position and captions drawn into the picture are done in your video editor or player, which reads this file.
Up to 10 hours or 5 GB per recording. The box on this page takes files up to 500 MB; larger ones continue on the upload page. 99+ languages, detected automatically.
Pricing
The preview is free. When the full transcript needs a pack, one-time packs are $4 for 500 minutes, $8 for 1,000 minutes, $12 for 2,000 minutes, $24 for 5,000 minutes. Credits never expire, which comes to about $0.29 to $0.48 per hour of audio.
| Recording | $4 or $8 pack | $12 pack | $24 pack |
|---|---|---|---|
| 3-minute explainer | $0.02 | $0.02 | $0.01 |
| 20-minute lesson | $0.16 | $0.12 | $0.10 |
| 1-hour webinar | $0.48 | $0.36 | $0.29 |
Figures are the share of a pack each recording uses. A button opens secure checkout for that pack. Every export format is included; full details on the pricing page.
FAQ
Upload the MP4 in the box on this page. When the transcript is ready, open it and download .vtt. The file is made from the speech in the video.
The preview is free. Opening or downloading the full transcript may need a pack; the smallest is $4 for 500 minutes and credits never expire.
No. The file contains the WEBVTT header and timed text only. Style captions with the ::cue selector in your page's CSS, or in your player's settings.
The usual causes are a track on a different domain without CORS headers, a page opened straight from disk, or an SRT file given to the track element, which accepts only WebVTT.
Yes. Both downloads come from the same transcript at no extra charge.
Every page in this set uses the same upload box and the same export. All subtitle pages
Free preview. VTT and SRT from the same upload; packs from $4 when the full transcript needs one.