From a recording to readable captions
- Choose your video. Use a file on your device. The page checks that it can read both the picture and sound.
- Generate, then review. Choose the spoken language, download the local speech model, and let it transcribe. Correct names, punctuation and timing. Click a timestamp to hear the passage again.
- Pick a look and save. Choose Classic, Boxed or Bold, adjust the size and position, then save a captioned MP4. Download SRT or VTT for use in another editor.
Your ears make the final edit
Automatic captions are a first draft. Music, overlapping speakers, quiet speech, accents and unfamiliar names can all change the words the model hears. Listen while you review, and check numbers against the original recording. Choosing the spoken language can help when a short clip is difficult to detect.
The captions follow phrases, with up to two visible lines. If an edited phrase becomes too long, shorten it, split it into separate captions, or choose a smaller size before saving video. SRT and VTT keep the full reviewed text.
Captions in the picture, or a separate file?
A captioned MP4 is ready for places where subtitles need to be visible for everyone. The words become part of the picture. SRT and VTT stay separate, so a compatible player can switch them on and off, and another editor can change their style.
This tool transcribes the language spoken in the recording. It does not translate, identify speakers, or animate individual words. Keep your original video so you can return to it for another edit.
Frequently asked questions
Is this subtitle generator free?
Yes. Generate, edit and save captions without an account, watermark or paid unlock. There is no imposed length cap, but longer videos take more time and available device memory limits what can finish.
Does my video leave my device?
No. Your video, audio and captions stay in this page’s memory. The page downloads its speech model and processing engine from CoProd when needed. It does not upload your media or save your work in browser storage. Explicit downloads are files you choose to save.
Can I generate English and French subtitles?
Yes. Choose the spoken language or use Auto-detect. The multilingual model also supports the other languages listed in the tool. Accuracy varies by language, accent, noise and recording. Review every caption, especially names and numbers. This transcribes the spoken language; it does not translate.
What is the difference between MP4, SRT and VTT?
The MP4 has your chosen caption style permanently drawn into the picture. SRT and VTT are separate UTF-8 text files with words and timestamps for another player or editor. They do not include the visual style you selected here.
Which videos and browsers work?
Use a current Chrome on a computer for the most reliable H.264/AAC MP4 support. MP4, MOV and WebM depend on the codecs your browser can decode. The tool checks the actual tracks before downloading the speech model. If video encoding is unavailable, you can still download SRT and VTT after generating captions. Physical phone compatibility has not yet been verified.
Will the saved video look exactly like the original?
The tool preserves the timeline and aspect ratio and keeps the primary sound track. It re-encodes the picture to H.264, upright, at up to 60 frames per second and 1080 pixels on the shorter side. HDR becomes SDR. Check the saved result before publishing.
Can I leave the tab or come back to my captions later?
Switching to another tab stops an active processing job. Completed captions stay in the open page, but closing or refreshing loses them. Download an SRT or VTT copy to keep your reviewed wording and timing. There is no autosave or reliable offline reload.
Updated October 25, 2026