# Subtitles King

> Add AI-generated subtitles to any video. MCP server, REST API, and
> self-hostable open-source binary. Built for developers, AI agents,
> and humans.

## What it does

Upload a video → we compress it with ffmpeg → run OpenAI Whisper for
transcription → burn subtitles back into the video with ffmpeg → return
both the burned video and an SRT transcript.

## How to use it

### Hosted MCP server (no install)

Streamable-HTTP MCP endpoint at:

  https://brains.subtitlesking.com/mcp

Register in any MCP-compatible client (Claude Code, Claude Desktop,
Cursor, Windsurf, etc.):

  claude mcp add --transport http subtitlesking https://brains.subtitlesking.com/mcp

### Self-host MCP binary

Open-source Go binary. Install:

  go install github.com/kz-dev/subtitlesking/.../mcp-server@latest

Defaults to talking to the hosted backend. Override with env vars:

  SUBTITLESKING_URL=http://localhost:8080
  SUBTITLESKING_API_KEY=<your key>

### REST API

Base URL: https://brains.subtitlesking.com

Endpoints:
  POST /presign           — Get a presigned upload URL (X-API-KEY required)
  POST /upload            — Upload video via presigned URL
  POST /queue             — Poll status by authToken
  GET  /transcript        — Download SRT transcript
  GET  /download          — Download burned video

## MCP tools exposed

  add_subtitles_to_video      Upload a video, returns video_id + auth_token
  get_video_status            Poll status; returns transcript_url and download_url
  download_subtitled_video    Download the finished, subtitle-burned video
  get_transcript              Get the SRT transcript (HTTP MCP)
  download_transcript         Save the SRT to disk (stdio MCP)

## Pipeline status states

  new → compressing → compressed →
  generating_srt → srt_generated (transcript ready here) →
  burning_subtitles → subtitles_burned (video ready here)

## Free tier

- Videos up to 100 MB
- Hosted MCP and REST API access
- 24 h retention on processed files
- No signup required

## Pages on this site

  /                Homepage
  /mcp             MCP server overview and install
  /api             REST API overview
  /self-host       Self-hosting guide
  /try             Free upload UI
  /docs            Full documentation
  /blog            Articles and tutorials
  /vs              Comparisons with other transcription services
  /pricing         Pricing tiers
  /changelog       Release notes

## Source code

  https://github.com/kz-dev/subtitlesking

## Contact

  Created by Kirill Zubovsky — https://x.com/kirillzubovsky