Subtitle Translate

Translate an SRT or WebVTT file so every cue meets your CPS and line-length spec, with a review list.

Who it's for

Video producers, e-learning teams and agencies localising a 10-60 minute video into several languages, who today fix over-speed subtitle cues by hand.

What you get

Your SRT or WebVTT file translated into one language and returned in the same format, with every cue inside your spec for characters per second, characters per line and lines per cue (defaults 17 cps, 42 per line, 2 lines); cues shorter than the minimum duration (default 833 ms) are flagged or, on request, lengthened. Cue count, ids, timings, markup tags and WebVTT notes and settings are kept; line breaks are set for you.

Cues that overflowed after translation are shortened and listed as condensed, with their speed before and after. Cues that could only be cut are listed as lossy for review. The returned file is re-parsed and measured, so the report describes the file you receive, with a metrics line for every cue. A file that needs more than 10 percent of its cues cut is an error and is not charged. A second tool measures any subtitle file against a spec without translating it.

Example

"Translate this English SRT of our 24-minute training video into German, French and Dutch at max 17 characters per second and 42 characters per line, and tell me which cues you had to condense."

Limits

• SRT or WebVTT text, up to 1000 cues and 200000 characters; one target language per call, so three languages are three calls.
• Cue start and end times are never changed unless you ask for short cues to be lengthened. Source cues below the minimum duration are flagged.
• Subtitle text is processed in memory by Google Gemini; nothing is stored.

How to use

• Run it in Apify Console or through the API: choose what to do, fill in the fields for that tool and start. The result is one item in the run's dataset.
• From an AI assistant through Apify's MCP server (mcp.apify.com), which finds and runs this Actor with the same fields. What each choice does:
  • translate_subtitles: Translate one SRT or WebVTT file into one target language and return a file in the same format in which every cue meets the spec for characters per second, characters per line and lines per cue; source cues shorter than the minimum duration are flagged (or lengthened on request), never silently moved.
  • check_subtitle_spec: Measure an SRT or WebVTT file against a reading-speed and layout spec without translating it.

Pricing

• Translate subtitles to fit a spec: $0.24
• Block of 50 subtitle cues: $0.24
• Check subtitles against a spec: $0.059

Failed calls are never charged.