MiniMax H3

MiniMax H3 (Hailuo 03) modes, input limits, defaults, prompt cap, credit pricing, and API examples.

Overview

Vendor: MiniMax. minimax-h3 (Hailuo 03) generates 4–15 second clips from text, an image, first and last frames, reference images, or a source video. It supports all five modes.

Prompts are limited to 7000 characters after trimming. The catalog lists this as max_prompt_length. Longer prompts return 400 with minimax-h3 prompt must be 7000 characters or fewer, got <length>.
No audio toggle: audio: true is rejected.

Modes and inputs

Mode	`image_urls`	`video_urls`	Aspect ratios	Defaults
`text-to-video`	None	None	21:9, 16:9, 4:3, 1:1, 3:4, 9:16	4s, 768P, 16:9
`image-to-video`	Exactly 1 (first frame)	None	Follows the image (omit)	4s, 768P
`frames-to-video`	Exactly 2 (first, last)	None	Follows the images (omit)	4s, 768P
`reference-to-video`	1–4	0–1	21:9, 16:9, 4:3, 1:1, 3:4, 9:16	4s, 768P, 16:9
`video-to-video`	0–2 (references)	Exactly 1	21:9, 16:9, 4:3, 1:1, 3:4, 9:16	4s, 768P, 16:9

Every mode accepts durations 4s, 6s, 8s, 10s, 12s, 15s and resolutions 768P, 2K.

When you send video_urls, also send options.source_video_duration_seconds (the source clip's length in seconds). It is required but does not change the price.
video-to-video generates a new clip guided by the source video. It is not a frame-accurate edit of the source.
Reference audio is not accepted through the API.

Credit pricing

Charge = rate × duration, in every mode. Video input does not change the rate.

Resolution	Credits per second	4s	6s	8s	10s	12s	15s
768P	3	12	18	24	30	36	45
2K	4	16	24	32	40	48	60

Example

curl -X POST https://viewmax.studio/api/v1/videos \
  -H "Authorization: Bearer $VIEWMAX_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: h3-example-0001" \
  -d '{
    "model": "minimax-h3",
    "mode": "text-to-video",
    "prompt": "Slow aerial shot over terraced rice fields at sunrise, mist between the hills",
    "options": { "duration": "6s", "resolution": "2K", "aspect_ratio": "16:9" }
  }'

This request costs 24 credits.

With a source video:

curl -X POST https://viewmax.studio/api/v1/videos \
  -H "Authorization: Bearer $VIEWMAX_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: h3-example-0002" \
  -d '{
    "model": "minimax-h3",
    "mode": "video-to-video",
    "prompt": "Same camera move, but at night with neon signs",
    "video_urls": ["https://example.com/source.mp4"],
    "options": {
      "duration": "10s",
      "resolution": "768P",
      "source_video_duration_seconds": 8
    }
  }'

This request costs 30 credits. With MCP, call generate_video with model: "minimax-h3".

Notes

Resolution values are case-insensitive; the catalog spells them 768P and 2K.
Omitted options use the defaults above and are billed at those values.