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How to translate subtitles on a Mac without uploading them
By Himanshu Ranjan · Updated 8 November 2026
Select the subtitle file in Finder, open FileDial, and run Translate › Translate subtitles… It translates on this Mac and keeps the timings, so you get a new subtitle file in another language without uploading the script. Machine translation can be wrong, so check anything important.
What the tool does
FileDial's Translate › Translate subtitles… translates the text of a subtitle file on this Mac and keeps the timings. That means the cues appear at the same moments as in the original, only with different words. The original file is untouched and the translation is a new copy.
Doing this on-device matters for scripts that are not public yet, and for client work that comes with confidentiality terms.
Translate with FileDial
- Select the .srt or .vtt file in Finder.
- Hold the right Option key to open the dial.
- Choose Translate › Translate subtitles… and pick the language when asked.
- Open the new file and check it in your player.
Check the translation
Machine translation is quick but not perfect. Idioms, jokes, names, technical terms and very short lines are the usual trouble spots. Review a few minutes of the result against the video before you publish. Subtitle translation has its own constraints too, since text must fit on screen and be read in a short time, and the translated line can be longer than the original. Be ready to edit long lines in a text editor.
Working with other formats
If your source is not SRT, convert first with Convert › Convert to SRT. If the translation must go into a web player, convert it with Convert › Convert to WebVTT. To attach multiple languages to a video, Combine › Add subtitle track adds a switchable track without re-encoding, which suits closed subtitles that viewers can turn on, or off, and switch between languages without changing the video.
If you start from audio
Without any subtitles, make them with Convert › Transcribe to subtitles…, which produces an SRT and a TXT on this Mac, then translate the SRT.
Quality limits of machine translation for subtitles
Subtitles are hard to translate well because each cue is short and out of context. A line such as Right? or He said no may have several meanings that only the surrounding cues clarify. Humor, wordplay, slang and cultural references usually lose something, and names of people, products and places need checking. Gendered and formal forms differ between languages, and a translator working line by line can pick the wrong one.
For these reasons, treat the output as a draft for private viewing or as a base for a human translator, rather than as a finished product for an audience. Where the stakes are high, such as legal, medical or published material, have a fluent speaker review it.
Preparing the file for a better result
Start from a clean source. If the original has typos, fix them first, because errors get translated faithfully. Make sure line breaks do not split a sentence in a way that confuses meaning, and that the file is in good order, using Edit › Fix numbering if the cues are mixed up. Convert to SRT first with Convert › Convert to SRT if the source is another format, so the file is in the most widely used structure.
After translation, play the result with the video. Watch for lines that are too long to read in the time they are on screen, because translated text is often longer. Shorten those by hand in a text editor. If timing needs adjusting because a long line needs more time, change cues or use Edit › Shift timing… for constant shifts.
Mistakes and honest limits
Do not assume the translated file is right because it has the same number of cues. Do not merge translations into one file for several languages, and keep one file per language with a clear name. Do not forget the encoding for languages with non-Latin scripts: a UTF-8 file is the safe choice, and the WebVTT specification requires it.
FileDial's translate tool is about private, on-device work. If you need professional-grade subtitle translation with glossaries and reviewers, a human service is the better choice, and you can still use the on-device draft as a starting point.
Reviewing by role
A good review has two passes. The first is for meaning: someone who understands both languages reads the translation without the video, looking for lines that do not make sense. The second is for fit: someone plays the video and watches whether each line can be read in time, whether line breaks fall in sensible places, and whether the tone matches the speaker. Keep a list of fixed terms, such as product names, and apply them consistently across all the files. If you ship several languages, number the versions in the file names so that a corrected file does not get confused with an older one.
Why on-device
No upload means no third party sees your script. FileDial runs every tool on your Mac and never uploads a file, and all tools work with Wi-Fi off.
Questions
Are my subtitles uploaded when translating?
No. FileDial translates on this Mac and every tool works with Wi-Fi off. The licence check and optional anonymous usage counts are the only things that go online, and never file names or contents. The same applies to the subtitle text itself, which stays on the Mac while it is translated.
Are the timings preserved?
Yes. The tool note says translated on this Mac, timings kept. Cues appear at the same moments with the new text, though long translated lines may need a manual edit to fit the screen. Cue timings are kept as they were, but longer translated lines may stay on screen too briefly and need editing.
Is machine translation accurate enough to publish?
Treat it as a first draft. Check names, idioms and technical words, and have a fluent speaker review anything public or important. Names, jokes and technical terms are the usual trouble spots, so read the result against the video before you share it.
Can I translate several files at once?
Yes, select multiple subtitle files in Finder and run the tool once. Confirm the language prompt applies to the whole batch before you publish them. Pick the language when prompted and confirm it fits the whole selection, since the same choice applies to every file in the run.