Updated 2026-07-02 - Verified with SubPlayer v0.5.17
What does "local" actually mean?
Three different setups get called "local", and they behave very differently:
- Fully local: subtitle editors such as Subtitle Edit. Core editing sends nothing anywhere; optional online services vary by tool.
- Hybrid: SubPlayer. Audio transcription runs on your PC; only the plain subtitle text goes to the cloud for translation.
- Fully online: browser-based video translators. The movie, the audio or at least the subtitle file is uploaded to someone else's server.
| Workflow | Data sent online | Works without internet | Best for |
|---|---|---|---|
| Local subtitle editor | Nothing for core editing; optional services vary | Yes | Detailed editing |
| SubPlayer | Subtitle text for translation; licensing and optional diagnostics | Processing is local; licence or API key still required | Watching movies |
| Online video translator | Usually the uploaded media or subtitle files | No | Creator exports and publishing |
Which questions should you ask before choosing?
- Does the movie or audio leave the device? Uploading multi-gigabyte files takes time and hands the file to someone else's server.
- Is subtitle text retained after processing? Check the service's terms; policies vary.
- Is the tool made for watching, editing or publishing? A mismatch here wastes the most time.
- What still works without internet?
- Can uploaded data be deleted, and is that documented?
Where does SubPlayer sit?
SubPlayer is built for watching, and honesty matters here: it is not "100% private". The video file and the audio never leave your computer - playback and transcription are local. When you translate, the plain subtitle text is sent to the cloud translation service, plus license checks and optional diagnostics. SubPlayer does not intentionally store subtitle content in its application database; provider-side temporary logging may apply under the provider's terms. Plain-language details: local processing.
When is an online tool the better choice?
When you publish videos. Creator platforms produce hardcoded or embedded subtitles, export many formats and run on any operating system. If the goal is a subtitle file for an audience rather than for tonight's movie, an online workflow fits better.
When is a local editor the better choice?
When you need precision: frame-accurate timing, line-break rules, batch fixes across many files, quality checks. Editors are made for that job; a player is not.
Frequently asked questions
Is SubPlayer fully offline?
No. Audio processing runs locally, but the subtitle workflow still needs an active licence or your Gemini API key; translation needs internet and sends subtitle text.
Is uploading a whole movie to a website slow?
Movie files are usually several gigabytes, so upload time depends entirely on your connection. That is one practical reason watch-focused tools avoid uploading media.
Do online tools keep my files?
Policies vary by service. Read the retention terms before uploading anything you would not want stored.
Why not just download a ready SRT?
That works when a matching file exists for your exact release and language. When it does not, translating an existing track or generating subtitles from audio fills the gap.
Related guides
Translate an SRT file on Windows
The full workflow for an existing subtitle file.
Generate subtitles from movie audio
Local audio processing; licence or API-key access still applies.
Comparison hub
SubPlayer vs VLC, Subtitle Edit and online workflows.