# Seedance 2.5 Text to Video - Core.Today AI API

> ByteDance Seedance 2.5 text-to-video via Fal.AI. Generates a native single-shot clip of up to 30 seconds at 480p/720p from a text prompt alone, reasoning about the whole shot at once so motion, lighting, and subject identity stay coherent from first frame to last. Synchronized audio (dialogue, sound effects, music) is generated in the same pass.

- **Provider**: ByteDance
- **Model ID**: bytedance/seedance-2.5/text-to-video
- **Category**: Video Generation
- **Credits**: 5500 per 5s 720p video — billed per second (480p 513/s, 720p 1100/s)
- **Speed**: Medium
- **Quality**: Ultra

## Features
- Native single-shot generation up to 30 seconds — no clip stitching
- Synchronized audio generated with the video, including lip-synced speech
- 480p and 720p output tiers, priced per second
- Seven aspect ratios from 21:9 ultrawide to 9:16 vertical, or auto
- Multilingual prompts

## Use Cases
- Long-form single-take social clips that would otherwise need multi-shot stitching
- Narrated product or explainer videos where speech must match on-screen lip movement
- Concept and mood films generated straight from a written treatment
- Rapid 480p style exploration before committing to a 720p final render

## API Endpoint

Base URL: https://api.core.today/v1
Create Prediction: POST /predictions
Get Status: GET /predictions/{job_id}

## Authentication
Header: X-API-Key: YOUR_API_KEY

## Input Parameters

### Required
- **prompt**: string - The text prompt used to generate the video. For dialogue, put the spoken words in double quotes — the model generates matching lip movements and voice.
- **duration**: string - Duration of the video in seconds (4-30), sent as a string. Required — upstream also accepts "auto", but the resulting length is unknown at request time and cannot be billed accurately, so this gateway requires an explicit duration.
  Options: 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30

### Optional
- **resolution**: string (default: 720p) - Video resolution — 480p for faster generation, 720p for balance.
  Options: 480p, 720p
- **aspect_ratio**: string (default: auto) - The aspect ratio of the generated video. Use 16:9 for landscape, 9:16 for portrait/vertical, 1:1 for square, 21:9 for ultrawide cinematic, or auto to let the model decide.
  Options: auto, 21:9, 16:9, 4:3, 1:1, 3:4, 9:16
- **generate_audio**: boolean (default: true) - Whether to generate synchronized audio for the video, including sound effects, ambient sounds, and lip-synced speech. The cost of video generation is the same regardless of whether audio is generated.

## Examples

### Multi-scene prompt in one take
A single prompt describing a scene change; the model keeps subjects and style consistent across the cut.
```json
{
  "model": "bytedance/seedance-2.5/text-to-video",
  "input": {
    "prompt": "An octopus finds a football in the ocean and excitedly calls its octopus friends to come and play. Cut scene to an octopus football game under the sea.",
    "duration": "5",
    "resolution": "720p",
    "aspect_ratio": "auto",
    "generate_audio": true
  }
}
```

### Vertical 480p draft
Explore composition cheaply at 480p in a 9:16 frame before rendering the 720p master.
```json
{
  "model": "bytedance/seedance-2.5/text-to-video",
  "input": {
    "prompt": "A barista pours latte art in a sunlit cafe, close-up on the cup, warm morning light, gentle jazz in the background.",
    "duration": "6",
    "resolution": "480p",
    "aspect_ratio": "9:16",
    "generate_audio": true
  }
}
```

## Response Format
```json
{
  "job_id": "abc123",
  "status": "pending | processing | completed | failed",
  "result": "URL or data (when completed)"
}
```

## Usage Flow
1. POST /predictions with model and input -> receive job_id
2. GET /predictions/{job_id} -> poll until status is completed or failed
3. Result contains output URL(s)

## Tips
- duration is a string on this endpoint — send "5", not 5. Integers are rejected before the request reaches the provider.
- Billing is per second of output, so a 30-second take costs six times a 5-second one. Iterate short, finish long.
- Draft at 480p (roughly half the per-second rate) and re-render the keeper at 720p.
- Put dialogue in double quotes inside the prompt to get lip-synced speech instead of narration-style audio.

## Documentation
https://fal.ai/models/bytedance/seedance-2.5/text-to-video