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How to convert SRT to VTT on a Mac
By Himanshu Ranjan · Updated 8 November 2026
Select the .srt files in Finder, open FileDial, and run Convert › Convert to WebVTT. A new .vtt file appears beside each original, and nothing is uploaded. WebVTT is the format HTML5 video players use, so converting is usually needed when you publish a video on your own website.
Why web players want VTT
WebVTT is the W3C format for timed text used with the HTML5 track element. It grew out of SubRip, so it looks familiar, but it is not fully compatible with SRT. A WebVTT file must begin with the line WEBVTT, uses a full stop instead of a comma in timestamps, makes hours optional, and must be UTF-8 text.
Those differences are why you cannot simply rename movie.srt to movie.vtt and expect every browser to accept it. A proper conversion rewrites the header and the timestamps.
Convert with FileDial
- Select one or more .srt files in Finder.
- Hold the right Option key to open the dial.
- Choose Convert › Convert to WebVTT and release.
- Open the new .vtt beside each original. Undo on the result card removes it.
What carries over and what does not
The timing and text carry over. FileDial's tool note warns that styling, meaning fonts, colours and positions, is not carried over, which matters if your SRT used font tags for colour. Plain SRT files, which are the large majority, convert cleanly. WebVTT handles styling through separate CSS and cue settings, so if you need styling on the web, add it afterwards in a text editor.
Check the result before you publish
Open the VTT in a text editor: the first line should be WEBVTT and the timestamps should use full stops. Then test it with your player. If the timing is off, correct it with Edit › Shift timing… in FileDial, where a negative amount moves subtitles earlier. If the text shows odd characters, the original SRT was probably not UTF-8, because SRT has no official encoding and many older files use Windows-1252. Re-save the source as UTF-8 and convert again.
Other things you can do with the same file
If you want the subtitles inside a video rather than beside it, Combine › Add subtitle track adds a switchable track without re-encoding, and Combine › Burn in subtitles makes them part of the picture. The guide on adding subtitles to video covers both.
A worked example of what changes
Take the start of an SRT file: a line with 1, then 00:00:01,000 --> 00:00:03,500, then the text, then a blank line. In WebVTT the same cue becomes the header line WEBVTT, a blank line, then 00:00:01.000 --> 00:00:03.500 and the text. The comma became a full stop, the header was added, and the number may remain or go because cue identifiers are optional. Nothing about the words or the moments changed.
Knowing this helps you debug. If a browser shows no captions, open the VTT in a text editor and check three things: the first line, the full stops in the times, and UTF-8 encoding.
Using the VTT on your own site, and common mistakes
On a web page the file is attached to a video with an HTML track element, and the server should send it as text/vtt, the media type the W3C specification names. Hosting problems cause more failures than the file itself. Browsers can also refuse a subtitle file served from a different domain unless the server permits it, so test from the real page rather than from a local file.
The usual mistakes are converting a file that is not UTF-8 and getting garbled accents, renaming instead of converting, and expecting colours to survive. If you have several languages, convert each SRT and name the files clearly, for example film.en.vtt and film.fr.vtt. Rename › Rename with pattern… helps with batches, although it renames the originals, with Undo available.
When FileDial is and is not the right tool
FileDial is right when you have a handful of SRT files, want them converted privately on your Mac, or need to run a batch. If you need to edit the text, split cues or adjust line breaks, use a text editor or subtitle editor, then convert. The Mac has no built-in subtitle converter, but TextEdit can open an SRT as plain text for small fixes, provided you keep it in plain text format.
Testing the file in a browser
The fastest test is a local HTML page with a video element and a track element pointing at your VTT file. Serve the page from a local web server rather than opening it from disk, since browsers can restrict local files. If captions do not appear, open the browser's developer tools and check for a request error on the VTT, then check the header line and the encoding. Browsers show the captions only when the track is enabled, so set it to default or turn captions on in the player. Once it works, upload the same VTT, along with the video, to your site.
Private by default
Subtitle files can contain unreleased scripts. FileDial runs every tool on your Mac and never uploads a file, and all tools work with Wi-Fi off.
Questions
Can I just rename .srt to .vtt?
Not reliably. WebVTT needs a WEBVTT header line, full stops in timestamps and UTF-8 text, while SRT uses commas. Some players tolerate a rename, many do not. Convert › Convert to WebVTT in FileDial rewrites the file correctly. A converter also checks the timestamp format, which is where hand-renamed files usually fail.
Will styling survive the conversion?
No. FileDial's tool note says fonts, colours and positions are not carried over. Timing and text are kept. WebVTT styles through CSS and cue settings, so add styling afterwards if your web player needs it. Keep the SRT as your master, because the web version loses nothing that matters for plain subtitles but cannot go back to richer styling.
Do I need VTT for YouTube?
Not necessarily. YouTube accepts several formats, and SRT is commonly used. VTT is chiefly for HTML5 players on your own pages. Check the platform's current upload options before converting. For YouTube-style uploads you can usually provide SRT directly, so convert only when a web player or form asks for VTT.
Can I convert many SRT files at once?
Yes. Select them all in Finder and run Convert › Convert to WebVTT once. FileDial saves a new .vtt beside each .srt and keeps the originals. A batch is useful when you have one file per language or episode, since every file gets its own VTT beside it.