Translation Guide

Translate Subtitles and Prepare an Engine

Choose an engine that is ready on your device before starting. The available languages and any required downloads depend on that engine.

Apple Translation

Requires iOS 18 or later. Supported languages are shown on your device. Choose a language pair in Translation Management and follow the system prompt to download its language resources.

DeepL API

Requires your own API key, a matching Free or Pro API plan, and a network connection. Availability depends on your account and remaining quota.

Google Web

No API key is needed. Your device must be able to connect to Google services. Network restrictions, service limits or temporary outages can cause failures.

Subtitles → Translation → Choose engine and target language → Start Translation

Subtitle translation detects the source language automatically. The Translation button handles all rows in the current subtitles. In selection mode, it only translates the rows you select.

After a successful translation, the translated text is saved and playback switches to bilingual display. Review the wording and edit any lines that need correction.

If translation fails or is cancelled, the unfinished results from that attempt are not applied. Resolve the reported problem and start again.

Google Web and DeepL send the subtitle text being translated to their respective online services.

Use Translation Test in Translation Management to check language resources, the API key and the connection with a short piece of text before translating a whole video.

Choose Original, Translated or Bilingual Display

Use the display menu on the Subtitles tab to choose Original, Translated text or Bilingual. Bilingual places the original above its translation.

Off hides subtitles on the video picture while leaving the subtitle list available. When only some rows are translated, untranslated rows continue to show the original text.

What should I check if translation fails?

For Apple, check supported languages and downloaded language resources. For DeepL, check the API key, plan and quota. For online engines, check the connection. Use Translation Test before retrying the subtitles.