How to Add Subtitles to a Video

Step 1: create the subtitle file

1. Open the subtitle generator and switch Full translation output off.
2. Drop in your video. Select the spoken language for untranslated subtitles, or another language for translated subtitles.
3. Download the SRT (for uploads and editors) and the VTT (for web players).
4. Open the SRT in a text editor and fix any names or terms.

YouTube

YouTube Studio → Subtitles → choose the video → Add language → Upload file → With timing → select the .srt. Repeat for each language. More in the YouTube subtitle guide.

Your website (HTML5 video)

Add a track element inside the video tag, pointing at the VTT file: <track src="captions-en.vtt" kind="subtitles" srclang="en" label="English" default>. Serve the file as text/vtt. Details in the VTT generator page.

Premiere Pro, DaVinci Resolve and Final Cut

• Premiere Pro: File → Import the .srt, then drag it onto the timeline above your video as a caption track.
• DaVinci Resolve: import the .srt into the Media Pool and drag it onto the timeline; it becomes a subtitle track.
• Final Cut Pro: File → Import → Captions, then choose the .srt.

Editors are also where you can burn subtitles permanently into the picture, if a platform doesn't support caption files. mydubly itself delivers subtitle files, not burned-in subtitles.

VLC and other players

Give the .srt the same name as the video (holiday.mp4 and holiday.srt) and put them in the same folder — VLC loads it automatically. Or use Subtitle → Add Subtitle File.

Social platforms

LinkedIn and Facebook accept SRT uploads for video posts. Many short-form apps don't accept subtitle files at all, so creators burn captions in with an editor before posting.

Pick the right subtitle file first

mydubly delivers subtitles as separate SRT and VTT files and never burns them into the picture. Which run you take them from decides whether they match the audio:

Original audio, same-language captions

Transcript mode with the spoken language selected. Subtitles come back untranslated, in the spoken language.

Original audio, translated subtitles

Transcript mode with a target language. Subtitles carry the full translation.

Dubbed video

Use the SRT or VTT from the dub-mode run. They follow what the voice actually says, including lines shortened to fit timing, so text and voice agree.

Mixing these up causes the most common complaint: transcript-mode subtitles on a dubbed video sometimes show a longer sentence than the voice speaks. If you publish both an original and a dubbed version, name the two files distinctly, for example by adding -dub to the dubbed one, so they never get swapped during upload.

A five-minute check before attaching the file

1. Open the SRT in a plain-text editor rather than a word processor, which can add hidden formatting. It should begin with cue 1 and a timing line such as 00:00:01,000 --> 00:00:03,500.
2. If you edit it, save as UTF-8. Other encodings are the usual reason accented letters and non-Latin scripts turn into symbols; see subtitles show strange characters.
3. Jump to the last cue and confirm its end time isn't later than the video's length. If it is, you transcribed a different cut.
4. Correct names and terms, keeping each cue short enough to read comfortably.
5. Name the file for where it's going, as described in the next section.
6. Load it in a desktop player such as VLC and watch the first and last minute with subtitles on. Problems are much cheaper to spot here than after publishing.

How to edit an SRT file walks through safe edits that won't break the timing lines.

Naming sidecar files and setting languages

Desktop players and media servers usually find subtitles by file name. A widely used pattern is the video's name, a language code, then the extension:

• lecture-04.mp4 alongside lecture-04.en.srt and lecture-04.es.srt gives a player two tracks to offer.
• In an HTML5 page, the language goes in the track element's srclang attribute (en, es, pt-BR), and the label attribute is what viewers see in the menu.
• Upload forms such as YouTube's ask for the language separately, so the name matters less there, but a clear name stops you uploading the Spanish file under French.

Conventions differ between players and media servers, so check your player's documentation for its exact rules. The trade-offs between separate files and tracks stored inside the video are explained in embedded vs sidecar subtitles.

Fixing subtitles that won't behave

Nothing appears

Subtitles may be switched off in the player menu, or the file name doesn't match the video. On a website, confirm the VTT starts with WEBVTT and is served from the same site or with cross-origin headers.

Every cue is early or late by the same amount

The video was trimmed after transcription. Shift all cues with a subtitle editor's offset tool, or transcribe the final cut.

Drift that grows through the video

The published file differs from the transcribed one, often after a frame-rate conversion. Transcribe the exact file you publish.

Upload rejected

Check that the extension is .srt rather than .srt.txt and that editing didn't leave the file empty or with a broken timing line.

Too much text on screen

Split long cues in a subtitle editor; subtitle readability gives practical limits.

Still stuck? SRT file not working covers platform-specific causes.

When a platform won't accept a subtitle file

Some short-form apps ignore sidecar files entirely. mydubly doesn't burn subtitles in, so open captions for those platforms are made in a video editor: import the SRT as a caption track, style it, and export with the captions rendered into the picture. Keep the SRT afterwards, because the same file still serves YouTube, your website and future re-edits. For YouTube specifically, the YouTube subtitles page covers uploading one track per language.