How to translate subtitles into other languages on your Mac

Why translate subtitles?

Because most of the people who could watch your video do not speak its language. Subtitles are the lightest way to reach them: the picture and the voice stay as they are, and a viewer picks the language they read best. They also help people watching with the sound off, and they give search engines and platforms words to index in each language.

Subtitles are cheaper than dubbing and keep the speaker's own voice. AI dubbing compares the two, and what is an SRT file explains the subtitle files themselves.

How can you translate the subtitles of a video?

Three ways, from quickest to most careful:

Method	How it works	Good for
Machine translation, unread	Each caption is run through a translator and published	Nothing public: errors go out under your name
Machine translation, then review	A translator makes the draft; a fluent speaker corrects it	Most creators and businesses
A professional subtitler	A person translates, condenses and times every caption	Films, broadcast, legal and medical content

Whichever you choose, the steps are the same:

Get the source right. Every error in the transcript is translated faithfully into every language. Fix names and terms first.
Translate whole captions, not individual lines, so a sentence split over two lines keeps its grammar.
Re-break the lines. A translation is often longer, so it needs new line breaks to stay readable.
Keep the timing. Each caption stays on screen for the same stretch as the words it carries.
Check the reading speed. A longer translation in the same time can be too fast to read.

How do you check a machine translation?

Read it with the video, not as a list. Machine translation gets most sentences right and some badly wrong, and the wrong ones are often confident and fluent. Look for:

Idioms and short commands, which are translated literally. "Pin your plugins" came back in Spanish as "catch your plugins" and in French as "paste your plugins".
Names, products and terms, which may be translated when they should not be.
Captions that run too fast. Netflix's English guide allows up to 20 characters a second for adult programmes, and its guides for other languages set their own limits. Netflix's subtitle template guide lists ways to fit, such as deleting, reformulating, re-timing or merging captions, and warns against condensing more than needed.
Tone. Formal or informal "you" in French, German or Spanish changes how a video feels.

A young woman in headphones watches a laptop closely at a wooden table by a window, one hand on the trackpad. — A fluent speaker reading the translation against the picture catches what no translator flags.Photo by Andrea Piacquadio on Pexels

How do you translate subtitles in Sharpy?

In one request, on your Mac, after the edit is made:

Make sure the words are right in the original language. Sharpy transcribes in the language you name, or the one it hears where speech begins, and tells you how sure it is; below half sure, it asks you to name it. Measured on Google's FLEURS recordings on the base Mac mini M4 with 16 GB, it gets 3.81% of words wrong in Spanish, 5.35% in French, 3.56% in German and 4.45% in English. Fix names and terms before you translate.
Ask for the languages when you render. Tell the agent "render with Spanish and French subtitles", and Sharpy translates each caption whole, re-breaks it into readable lines and keeps its timing. If your Mac does not have a language yet, the window downloads it when you ask.
Read the list Sharpy prints. Translations run longer, so Sharpy lists every caption that breaks its reading rules once translated. Fix those first.
Read the rest with the video. Every translated track is labelled machine translation, because it is.
Check against a receiver's rules if you deliver to one. The agent's check_captions holds an SRT or WebVTT file to the published rules of Netflix, Prime Video, the BBC, DCMP or ESIST, and names every caption that breaks one, with what it measured and whose rule it is.

A talking head with no captions on the picture still gets subtitles in every language, made from every word through its cuts and speed changes. Nothing is uploaded: the transcript, the translation and the files are all made on the Mac.

Can you add subtitles in multiple languages?

Yes, in two forms, and most videos want both:

Tracks inside the video. Sharpy puts every language into the movie as its own subtitle track, tagged with its language so a player's subtitle menu lists them by name. None is switched on until the viewer chooses it.
Files beside the video. Each language is also written as SRT and WebVTT, named by its language code: the Spanish files end .es.srt and .es.vtt. Platforms such as YouTube take these files rather than tracks inside the video.

Keep the language code in every file name, so nobody uploads French as German. Burned-in captions, drawn on the picture, can carry only one language, so keep them for the main audience and give everyone else a file. Captions on your Mac covers both kinds.

How do you upload subtitles in several languages to YouTube?

One language at a time, from YouTube Studio. YouTube's help gives these steps:

Open YouTube Studio and choose Subtitles from the left menu.
Choose the video, then click Add language and pick the language.
Under Subtitles, click Add, choose Upload file, then With timing.
Select that language's SRT file and save.
Repeat for each language.

Translate the title and description too: YouTube's help explains adding a translated title and description for each language from the same Subtitles page, so viewers find the video in their own language as well as read it.

Frequently asked questions

How can I translate the subtitles of a video?

Translate each caption from an accurate transcript, keep the original timing, re-break the lines, and save one file per language. Sharpy does all of this on your Mac; then have a fluent speaker read the result.

Can I add subtitles in multiple languages?

Yes. Add one subtitle track or file for each language. Sharpy writes a track per language inside the video and an SRT and WebVTT file for each beside it.

Can I translate an SRT file directly?

Yes, by translating the words and leaving the numbers and times alone. Check the line lengths afterwards, because translations usually run longer.

Is machine translation good enough for subtitles?

As a draft, yes; published unread, no. Idioms, names and tone go wrong in ways a fluent reader spots at once.

Do translated subtitles need different timing?

Usually the same timing with different line breaks. Where a translation is too long to read in the time, shorten the wording rather than stretching the caption past its speech.

Sources

Checked on 18 October 2026.