Rast Creator Tools

Returns the approximate areas of a vertical (9:16) video frame that the app interface covers on Instagram Reels, TikTok, YouTube Shorts or Instagram Stories: unsafe margins in pixels and percent, the safe rectangle for text, the position of the right-hand button column and short placement guidance. Values are measured on 1080x1920 and scaled to the given frame size.

{
  "type": "object",
  "properties": {
    "platform": {
      "type": "string",
      "enum": [
        "reels",
        "tiktok",
        "shorts",
        "story",
        "all"
      ],
      "description": "Vertical video platform: 'reels' (Instagram Reels), 'tiktok', 'shorts' (YouTube Shorts), 'story' (Instagram Stories) or 'all' (the strictest margins of all four combined)."
    },
    "width": {
      "description": "Frame width in pixels. Default 1080.",
      "type": "integer",
      "exclusiveMinimum": 0,
      "maximum": 20000
    },
    "height": {
      "description": "Frame height in pixels. Default 1920.",
      "type": "integer",
      "exclusiveMinimum": 0,
      "maximum": 20000
    }
  },
  "required": [
    "platform"
  ],
  "$schema": "http://json-schema.org/draft-07/schema#"
}

Checks whether a rectangular text box (caption, title or logo) on a vertical video frame stays inside the safe zone of Instagram Reels, TikTok, YouTube Shorts or Instagram Stories. Reports which interface element it overlaps (top bar, bottom caption area, right button column, edge margins, optionally the Reels comment-reply sticker) and suggests the nearest position that clears them. Coordinates are pixels from the top-left corner of the frame.

{
  "type": "object",
  "properties": {
    "platform": {
      "type": "string",
      "enum": [
        "reels",
        "tiktok",
        "shorts",
        "story",
        "all"
      ],
      "description": "Vertical video platform: 'reels' (Instagram Reels), 'tiktok', 'shorts' (YouTube Shorts), 'story' (Instagram Stories) or 'all' (the strictest margins of all four combined)."
    },
    "x": {
      "type": "number",
      "description": "Left edge of the text box in pixels, measured from the left of the frame."
    },
    "y": {
      "type": "number",
      "description": "Top edge of the text box in pixels, measured from the top of the frame."
    },
    "width": {
      "type": "number",
      "exclusiveMinimum": 0,
      "description": "Text box width in pixels."
    },
    "height": {
      "type": "number",
      "exclusiveMinimum": 0,
      "description": "Text box height in pixels."
    },
    "canvas_width": {
      "description": "Frame width in pixels. Default 1080.",
      "type": "integer",
      "exclusiveMinimum": 0,
      "maximum": 20000
    },
    "canvas_height": {
      "description": "Frame height in pixels. Default 1920.",
      "type": "integer",
      "exclusiveMinimum": 0,
      "maximum": 20000
    },
    "include_comment_sticker": {
      "description": "Reels only: also test against the comment-reply sticker band (approximately y 300-560 px on 1080x1920). Default false.",
      "type": "boolean"
    }
  },
  "required": [
    "platform",
    "x",
    "y",
    "width",
    "height"
  ],
  "$schema": "http://json-schema.org/draft-07/schema#"
}

Calculates the file size of a video export from its duration and bitrate, or (when target_size_mb is given) the highest video bitrate that fits that size with a 2% safety margin. Without an explicit bitrate it uses the reference value for the platform, resolution and frame rate (YouTube and Vimeo recommendations, Apple ProRes target data rates, or Rast's delivery target for Instagram and TikTok, which publish none). Also returns size-limit warnings (Meta 4 GB, TikTok ads 500 MB / 516 kbps) and a two-pass ffmpeg command.

{
  "type": "object",
  "properties": {
    "duration_seconds": {
      "type": "number",
      "exclusiveMinimum": 0,
      "maximum": 864000,
      "description": "Video length in seconds (e.g. 90 for 1:30)."
    },
    "resolution": {
      "description": "'720p', '1080p' (also 1080x1920 vertical), '1440p', '2160p' (4K UHD) or 'dci4k' (4096x2160). Default '1080p'.",
      "type": "string",
      "enum": [
        "720p",
        "1080p",
        "1440p",
        "2160p",
        "dci4k"
      ]
    },
    "fps": {
      "description": "Frame rate, e.g. 24, 25, 29.97, 30, 50, 60. Default 30. 48 fps and above use the high-frame-rate tables.",
      "type": "number",
      "exclusiveMinimum": 0,
      "maximum": 240
    },
    "platform": {
      "description": "Delivery target used for the reference bitrate: 'youtube', 'youtube_hdr', 'vimeo', 'instagram', 'tiktok', or a ProRes flavour ('prores_proxy', 'prores_lt', 'prores_422', 'prores_hq', 'prores_4444', 'prores_xq'). Default 'youtube'.",
      "type": "string",
      "enum": [
        "youtube",
        "youtube_hdr",
        "vimeo",
        "instagram",
        "tiktok",
        "prores_proxy",
        "prores_lt",
        "prores_422",
        "prores_hq",
        "prores_4444",
        "prores_xq"
      ]
    },
    "video_bitrate_mbps": {
      "description": "Video bitrate in Mbps to calculate the file size with. Omit to use the platform reference value.",
      "type": "number",
      "exclusiveMinimum": 0,
      "maximum": 10000
    },
    "audio_kbps": {
      "description": "Audio bitrate in kbps; 0 = no audio. Default 320.",
      "type": "number",
      "minimum": 0,
      "maximum": 5000
    },
    "target_size_mb": {
      "description": "If set, calculate the maximum video bitrate that fits this file size in megabytes (1 MB = 1,000,000 bytes) instead of the file size.",
      "type": "number",
      "exclusiveMinimum": 0,
      "maximum": 10000000
    }
  },
  "required": [
    "duration_seconds"
  ],
  "$schema": "http://json-schema.org/draft-07/schema#"
}

Checks pasted SRT or WebVTT subtitle text and lists problems per subtitle: overlapping or out-of-order timings, gaps shorter than the minimum frame gap, reading speed (characters per second), line length, line count, too short or too long durations, and broken characters from a wrong encoding (mojibake such as 'é' or '’', with the probable correct text). Optionally returns a corrected SRT. The text is only processed for this response.

{
  "type": "object",
  "properties": {
    "srt_text": {
      "type": "string",
      "minLength": 1,
      "maxLength": 200000,
      "description": "Full text of the .srt or .vtt file."
    },
    "preset": {
      "description": "Rule set: 'netflix' (42 chars/line, 2 lines, 17-20 CPS, 0.83-7 s; default), 'vertical' (short-form vertical video: 32 chars/line, 2 lines, 17-20 CPS, 1-5 s) or 'children' (42 chars/line, 13-17 CPS).",
      "type": "string",
      "enum": [
        "netflix",
        "vertical",
        "children"
      ]
    },
    "fps": {
      "description": "Video frame rate used for the minimum gap. Default 25.",
      "type": "number",
      "exclusiveMinimum": 0,
      "maximum": 240
    },
    "min_gap_frames": {
      "description": "Minimum gap between subtitles in frames. Default 2.",
      "type": "integer",
      "minimum": 0,
      "maximum": 12
    },
    "include_fixed_srt": {
      "description": "Also return a corrected SRT (encoding fixed, overlaps trimmed, long single lines split, short subtitles extended). Default false.",
      "type": "boolean"
    }
  },
  "required": [
    "srt_text"
  ],
  "$schema": "http://json-schema.org/draft-07/schema#"
}

Returns recommended export settings for uploading a finished video to YouTube (SDR or HDR), Vimeo, Instagram Reels or TikTok, or for a ProRes archive master: container, codec, resolution, frame rate, bitrate, colour and audio, plus links to each platform's official spec page and a short step list that works in any editor.

{
  "type": "object",
  "properties": {
    "platform": {
      "type": "string",
      "enum": [
        "youtube",
        "youtube_hdr",
        "vimeo",
        "instagram_reels",
        "tiktok",
        "prores_master"
      ],
      "description": "'youtube', 'youtube_hdr', 'vimeo', 'instagram_reels', 'tiktok' or 'prores_master'."
    },
    "resolution": {
      "description": "'1080p' (default) or '4k'.",
      "type": "string",
      "enum": [
        "1080p",
        "4k"
      ]
    },
    "orientation": {
      "description": "'vertical' 9:16 (default) or 'horizontal' 16:9; changes the frame size given.",
      "type": "string",
      "enum": [
        "vertical",
        "horizontal"
      ]
    }
  },
  "required": [
    "platform"
  ],
  "$schema": "http://json-schema.org/draft-07/schema#"
}