# MiniMax H3 Fast API (MiniMax)

> MiniMax H3 Fast is an inference-accelerated build of MiniMax H3's open weights: the same text, frame and reference inputs and a synchronized soundtrack, at 480P or 768P, returned many times faster and for a fraction of H3's price.

Page: https://cheapergen.com/models/minimax/h3-fast · API reference: https://cheapergen.com/models/minimax/h3-fast/api · Live status and uptime: https://cheapergen.com/models/minimax/h3-fast/status

## Pricing
Struck-through price: Official MiniMax H3 API: MiniMax's official H3 API price at the same resolution, platform.minimax.io (MiniMax sells no H3 Fast, so this is the reference: MiniMax H3 768P $0.08 / s; at 480P, MiniMax H3 Max 480P $0.05 / s, MiniMax's only official 480P H3 tier). Prices verified October 18, 2026.

| Tier | Official MiniMax H3 API | CheaperGen | Save |
|---|---|---|---|
| 480P | $0.0500/s | $0.0369/s | 26% |
| 768P | $0.0800/s | $0.0546/s | 32% |

## Specs
- Base model: MiniMax H3 (open weights)
- Resolutions: 480P (about 850×480 at 16:9) · 768P (1344×768 at 16:9)
- Duration: 4–15 s (24 fps; clips can run up to ~0.6 s longer)
- Aspect ratios: 16:9 · 9:16 · 1:1 · 4:3 · 3:4 · 21:9
- Inputs: Text, first/last frame, up to 9 reference images, 3 videos and 3 audio clips
- Audio: Always on (included)
- Enable Safety Checker: Default true · can be set to false over the API

## Endpoints

### Text to Video — `POST https://cheapergen.com/api/v1/run/minimax/h3-fast/text-to-video`

| Param | Type | Required | Description |
|---|---|---|---|
| prompt | string | yes | Describe the shot: subject, action, camera movement, lighting and style. |
| aspect_ratio | string (enum) (16:9, 9:16, 1:1, 4:3, 3:4, 21:9) | no | Output frame shape. |
| resolution | string (enum) (480P, 768P) | no | Output resolution. Higher resolutions cost more per second. |
| duration | integer (4–15) | no | Length of the generated clip in seconds (4–15s). You pay per second. |
| seed | integer | no | Use the same seed and settings to reproduce a result. Leave empty for random. |
| enable_safety_checker | boolean | no | If set to true, the safety checker will be enabled. Content our Acceptable Use Policy prohibits stays blocked either way. |

```bash
curl -X POST https://cheapergen.com/api/v1/run/minimax/h3-fast/text-to-video \
  -H "Authorization: Bearer $CHEAPERGEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "prompt": "A paper boat drifts down a rain-filled gutter at dusk, the patter of rain and a distant tram bell",
  "aspect_ratio": "16:9",
  "resolution": "768P",
  "duration": 6
}'
```

### Image to Video — `POST https://cheapergen.com/api/v1/run/minimax/h3-fast/image-to-video`

| Param | Type | Required | Description |
|---|---|---|---|
| prompt | string | yes | Describe the shot: subject, action, camera movement, lighting and style. |
| image_url | string (URL) | yes | Image used as the opening frame. JPG/PNG/WebP, URL or upload. |
| end_image_url | string (URL) | no | Optional closing frame — the model animates between the two. |
| aspect_ratio | string (enum) (16:9, 9:16, 1:1, 4:3, 3:4, 21:9) | no | Output frame shape. Pick the one closest to your first frame. |
| resolution | string (enum) (480P, 768P) | no | Output resolution. Higher resolutions cost more per second. |
| duration | integer (4–15) | no | Length of the generated clip in seconds (4–15s). You pay per second. |
| seed | integer | no | Use the same seed and settings to reproduce a result. Leave empty for random. |
| enable_safety_checker | boolean | no | If set to true, the safety checker will be enabled. Content our Acceptable Use Policy prohibits stays blocked either way. |

```bash
curl -X POST https://cheapergen.com/api/v1/run/minimax/h3-fast/image-to-video \
  -H "Authorization: Bearer $CHEAPERGEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "prompt": "The flower opens slowly in the morning light, birdsong in the background",
  "image_url": "https://cdn.cheapergen.com/samples/portrait.jpg",
  "aspect_ratio": "16:9",
  "resolution": "768P",
  "duration": 6
}'
```

### Reference to Video — `POST https://cheapergen.com/api/v1/run/minimax/h3-fast/reference-to-video`

| Param | Type | Required | Description |
|---|---|---|---|
| prompt | string | yes | Describe the shot: subject, action, camera movement, lighting and style. |
| reference_image_urls | string[] (URLs) | no | Up to 9 images for characters, products, style or scene. Refer to them as @Image1, @Image2… The first 5 are included; each extra image adds a small fee. |
| reference_video_urls | string[] (video URLs) | no | Up to 3 MP4/MOV clips for motion, camera moves or effects (2–15 s each, 15 s in total, ≤ 50 MB each). Refer to them as @Video1, @Video2… Reference-video seconds are billed like output seconds. |
| reference_audio_urls | string[] (audio URLs) | no | Up to 3 MP3/WAV clips for voice, music or sound (2–15 s each, 15 s in total, ≤ 15 MB each). Refer to them as @Audio1, @Audio2… Needs at least one reference image or video. |
| aspect_ratio | string (enum) (16:9, 9:16, 1:1, 4:3, 3:4, 21:9) | no | Output frame shape. |
| resolution | string (enum) (480P, 768P) | no | Output resolution. Higher resolutions cost more per second. |
| duration | integer (4–15) | no | Length of the generated clip in seconds (4–15s). You pay per second. |
| seed | integer | no | Use the same seed and settings to reproduce a result. Leave empty for random. |
| enable_safety_checker | boolean | no | If set to true, the safety checker will be enabled. Content our Acceptable Use Policy prohibits stays blocked either way. |

```bash
curl -X POST https://cheapergen.com/api/v1/run/minimax/h3-fast/reference-to-video \
  -H "Authorization: Bearer $CHEAPERGEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "prompt": "The singer from @Image1 performs on the rooftop, following the camera move in @Video1, with the vocals from @Audio1",
  "reference_image_urls": [
    "https://cdn.cheapergen.com/samples/reference-1.jpg"
  ],
  "reference_video_urls": [
    "https://cdn.cheapergen.com/samples/reference-1.mp4"
  ],
  "reference_audio_urls": [
    "https://cdn.cheapergen.com/samples/reference-1.mp3"
  ],
  "aspect_ratio": "16:9",
  "resolution": "768P",
  "duration": 6
}'
```

## Getting the result
Jobs are async. Poll `GET https://cheapergen.com/api/v1/generations/{id}` until status is succeeded/failed/canceled, or pass `webhook_url`. Failed generations are refunded automatically.

## FAQ
**What is MiniMax H3 Fast?**
An inference-accelerated build of MiniMax H3's open weights, served on our own GPU inference for open-source models. It takes the same inputs as H3 and returns a 480P or 768P clip with sound many times faster. It is not a MiniMax release, and MiniMax does not sell it.

**How is it different from MiniMax H3?**
Faster and cheaper, up to 768P instead of 2K, and — because sampling is shortened — details can differ from MiniMax's own H3 for the same prompt. The comparison gallery on this page shows both, generated through our API with the same prompts and settings.

**How is H3 Fast priced?**
Per second of output video at 480P or 768P, with the soundtrack included. In reference-to-video, reference-video seconds are billed like output seconds and images after the fifth add a small fee. Failed generations are never charged.

**Why is the official price on this page MiniMax H3's?**
MiniMax doesn't sell H3 Fast, so there is no official H3 Fast price. We compare it with the official MiniMax H3 API price at the same resolution: H3 at 768P, and H3 Max at 480P, MiniMax's only official 480P tier.

**Can I use the output commercially?**
Yes, subject to MiniMax's usage policy and our Terms of Service.

MiniMax H3 Fast is an accelerated build of MiniMax H3, which is developed by MiniMax; the acceleration is not a MiniMax release. CheaperGen does not own the model.