1. Start from a subtitle file
Upload an existing SRT or VTT. If you only have the video, generate subtitles first: Pro handles videos up to 4 hours per file.
VideoText workflow guide
Translate Subtitles for Long Videos
Translate a full-length SRT or VTT file in one go, with every timestamp kept. Built for long videos: films, lectures and recorded events with thousands of cues, where pasting text into a chatbot truncates the file or breaks the format. Don't have subtitles yet? Generate them from the video first, up to 4 hours per file on Pro.
Fix Translate Long Video Subtitles timing and reading-speed issuesGenerate subtitles with readable line timingExport Translate Long Video Subtitles captions without timestamp drift
Where long subtitle translation usually goes wrong
- A long video's subtitle file has thousands of cues. Pasted into a chatbot, it gets cut off partway, cue numbers shift, or timestamps come back rewritten, and the result is no longer a valid subtitle file. Here each cue is translated in place, so the numbering and every timestamp stay exactly as they were.
- Cues are translated with the lines around them as context, so a sentence split across two cues reads naturally in the target language instead of word by word. Translated lines are re-wrapped to fit each cue.
- The translation runs as a job on the server, so a long file keeps translating if you switch tabs or close the page, and the result is waiting when you come back.
Translating subtitles for a long video
2. Choose the target language
Pick one of 69 languages.
3. Review names and terms
Check proper names, product names and technical terms, which are the usual places a translation needs a human decision.
4. Export with the original timing
Download the translated SRT or VTT. Upload it next to the original as a second subtitle track.
What comes back
Translated SRT with original timestamps
Same cue count, same numbering, same start and end times: only the text changes, so it lines up with the video immediately.
A second-language track
Add the translated file as an extra subtitle track on YouTube, Vimeo or your course platform alongside the original.
SRT or VTT, in either direction
Upload either format. Subtitle files up to 20 MB are accepted, many times the size of the subtitles for a 4-hour video.
A subtitle translator compared with pasting into a chatbot
| Feature | VideoText | Alternatives |
|---|---|---|
| Long files | Whole SRT or VTT translated as one job | Truncated or needs pasting in chunks |
| Timestamps | Kept exactly as in the source file | Can be rewritten or dropped |
| Cue numbering | Unchanged | Shifts when lines merge or split |
| Output | A valid SRT or VTT ready to upload | Text that needs rebuilding into a subtitle file |
Long videos that get translated
Films and documentaries
Translate the full-length subtitle file for distribution in other languages.
Lectures and courses
Offer full lessons in a second language without re-recording them.
Conference and event recordings
Publish multi-hour sessions with translated captions for an international audience.
Sermons and services
Provide translated subtitles for multilingual congregations watching recordings.
Subtitle edge cases that cause QA failure
CPS violation — splitting required
Eight words spoken in 1.2 seconds: "we need to fix this before the deadline" at 24 CPS. The line must be split into two display segments within the same timing window to hit the readable 14–17 CPS range.
Subtitle timing overlap
Block ending at 00:01:23,500 overlapping a block starting at 00:01:23,200 causes display flicker and rendering failure in most SRT players. A subtitle validator catches this before upload.
Mobile frame crop
A two-line subtitle with 44+ characters per line at default font sizes clips at the bottom of mobile video frames. The safe area for mobile subtitles is a single line, 38 characters maximum, positioned at 85% vertical height.
Burned caption rendering after encode
Font stroke weight, drop shadow depth, and subtitle vertical position all shift slightly after H.264 encoding. Captions that look correct in preview may become harder to read in the encoded file — requires a post-encode QA pass before publishing.
Platform-specific subtitle requirements
YouTube SRT requirements
UTF-8 encoding required. Maximum 1,500 subtitle blocks per file. Timestamp format: 00:00:00,000 (comma separator, not period). Files over 1,500 blocks need splitting before upload. YouTube auto-syncs uploaded SRT to audio — small timing offsets are corrected automatically.
TikTok caption behavior
TikTok generates its own auto-captions and displays them over uploaded SRT files in most cases. Burned captions are the reliable method for ensuring accurate captions appear on TikTok content. SRT upload works but TikTok may override it.
Instagram Reels caption handling
Instagram does not display soft subtitle tracks during autoplay in Feed or Reels. Burned captions are the only reliable method for ensuring captions appear for silent autoplay viewers. Instagram's built-in auto-caption feature can also be used after upload, but accuracy varies.
VTT vs SRT encoding difference
VTT uses period timestamp separators (00:00:00.000) while SRT uses commas (00:00:00,000). Swapping the separator character breaks parsing in most players. VTT files must begin with the WEBVTT header line — SRT files must not.
Subtitle workflow questions answered
Can I translate subtitles for a full-length film or a 3-hour lecture?
Yes. Upload the whole SRT or VTT file and it is translated as one job, with every cue number and timestamp kept. A file with thousands of cues takes longer than a short clip, but it runs on the server, so you can leave the page and come back to the result.
Will the timestamps change?
No. Only the text of each cue is translated. Start and end times and cue numbering stay exactly as they are in the source file, so the translation lines up with the video.
I only have the video. How do I get subtitles to translate?
Generate subtitles from the video first. Pro handles videos up to 4 hours per file. Then upload the SRT here and choose the target language.
How many languages are supported?
69 languages. Pick the target language before you start.
Why not paste the subtitles into ChatGPT?
Long subtitle files often exceed what a chat reply returns in one go, so the file gets cut off, and timestamps or cue numbers can come back changed. A subtitle translator keeps the file structure intact and returns a valid SRT or VTT.