# FLUX 3 Video API (Black Forest Labs)

> FLUX 3 Video from Black Forest Labs generates 5–20 second 720p videos with synchronized audio from text or a start and end frame, at one flat per-second price.

Page: https://cheapergen.com/models/bfl/flux-3-video · API reference: https://cheapergen.com/models/bfl/flux-3-video/api

## Pricing
Official list price source: BFL API list price for FLUX 3 Video at 720p ($0.15 per second, audio included). Prices verified 2026-10-16.

| Tier | Official | Cheaper Gen. | Save |
|---|---|---|---|
| 720p | $0.1500/s | $0.1425/s | 5% |

## Specs
- Resolution: 720p
- Duration: 5–20 s
- Aspect ratios: 16:9 · 9:16 · 1:1 · 4:3 · 3:4 · 21:9 · 2:1
- Audio: Yes (included)
- Status: Preview (BFL)

## Endpoints

### Text to Video — `POST https://cheapergen.com/api/v1/run/bfl/flux-3-video/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, 2:1) | no | Output image shape. |
| duration | integer (5–20) | no | Length of the generated clip in seconds (5–20s). You pay per second. |
| generate_audio | boolean | no | Generate synchronized sound, ambience and dialogue. No extra cost. |

```bash
curl -X POST https://cheapergen.com/api/v1/run/bfl/flux-3-video/text-to-video \
  -H "Authorization: Bearer $CHEAPERGEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "prompt": "A hot-air balloon drifts over Cappadocia at sunrise, the burner roars, the camera rises alongside the basket",
  "aspect_ratio": "16:9",
  "duration": 5
}'
```

### Image to Video — `POST https://cheapergen.com/api/v1/run/bfl/flux-3-video/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. |
| duration | integer (5–20) | no | Length of the generated clip in seconds (5–20s). You pay per second. |
| generate_audio | boolean | no | Generate synchronized sound, ambience and dialogue. No extra cost. |

```bash
curl -X POST https://cheapergen.com/api/v1/run/bfl/flux-3-video/image-to-video \
  -H "Authorization: Bearer $CHEAPERGEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "prompt": "Slow push-in as the flower opens from bud to full bloom",
  "image_url": "https://cdn.cheapergen.ai/samples/portrait.jpg",
  "duration": 5
}'
```

## 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
**How is FLUX 3 Video priced?**
FLUX 3 Video is billed per second of output at 720p; audio is included at no extra cost, and a silent clip costs the same. Failed generations are never charged.

**Is this the official FLUX 3 Video?**
Yes. Requests run on Black Forest Labs' FLUX 3 Video model through official API channels. BFL lists it as a preview model.

**Can I use the output commercially?**
Yes, subject to Black Forest Labs' terms and our Terms of Service.

FLUX 3 Video is developed by Black Forest Labs. Cheaper Gen. provides API access and does not own the model.