fal-model-guide

---
name: "fal-model-guide"
description: "Use for model selection decisions: - Comparing FLUX vs SDXL for image generation - Choosing video models by quality tier - Optimizing costs with appropriate model selection - Understanding model-specific parameters - Building production vs development pipelines"
license: "MIT"
---

## Quick Reference

| Category | Fast/Cheap | Balanced | Best Quality |
|----------|------------|----------|--------------|
| Image | FLUX Schnell | FLUX.1 Dev | FLUX.2 Pro |
| Video | Runway Turbo | LTX-2 Pro | Kling 2.6 Pro |
| Audio STT | Whisper Turbo | Whisper | Whisper Large v3 |
| Audio TTS | Kokoro | XTTS | ElevenLabs |

| FLUX Model | Endpoint | Steps | Use Case |
|------------|----------|-------|----------|
| FLUX.2 Pro | `fal-ai/flux-2-pro` | 28 | Production |
| FLUX.1 Dev | `fal-ai/flux/dev` | 28 | High quality |
| FLUX Schnell | `fal-ai/flux/schnell` | 4 | Fast iteration |

| Video Model | Duration | Audio | Speed |
|-------------|----------|-------|-------|
| Kling 2.6 Pro | 5-10s | Yes | Slow |
| LTX-2 Pro | 5s | Yes | Medium |
| Runway Turbo | 5-10s | No | Fast |

## When to Use This Skill

Use for **model selection decisions**:
- Comparing FLUX vs SDXL for image generation
- Choosing video models by quality tier
- Optimizing costs with appropriate model selection
- Understanding model-specific parameters
- Building production vs development pipelines

**Related skills:**
- For text-to-image: see `fal-text-to-image`
- For text-to-video: see `fal-text-to-video`
- For audio models: see `fal-audio`

---

# fal.ai Model Selection Guide

Comprehensive guide to selecting the right fal.ai model for your use case.

## Image Generation Models

### FLUX Family

| Model | Endpoint | Best For | Speed | Quality | Cost |
|-------|----------|----------|-------|---------|------|
| FLUX.2 [pro] | `fal-ai/flux-2-pro` | Production, best quality | Medium | Highest | $$$ |
| FLUX.1 [dev] | `fal-ai/flux/dev` | High quality, open-source | Medium | High | $$ |
| FLUX Schnell | `fal-ai/flux/schnell` | Fast iteration | Fast | Good | $ |
| FLUX LoRA | `fal-ai/flux-lora` | Custom trained styles | Medium | High | $$ |
| FLUX Realism | `fal-ai/flux-realism` | Photorealistic images | Medium | High | $$ |

**FLUX.2 Pro** - Latest and best quality
```typescript
const result = await fal.subscribe("fal-ai/flux-2-pro", {
  input: {
    prompt: "Professional product photo of a watch",
    image_size: "square_hd",
    num_inference_steps: 28,
    guidance_scale: 3.5
  }
});
```

**FLUX.1 Dev** - Best open-source option
```typescript
const result = await fal.subscribe("fal-ai/flux/dev", {
  input: {
    prompt: "A serene mountain landscape",
    image_size: "landscape_16_9",
    num_inference_steps: 28
  }
});
```

**FLUX Schnell** - Fast 4-step generation
```typescript
const result = await fal.subscribe("fal-ai/flux/schnell", {
  input: {
    prompt: "Quick concept sketch",
    num_inference_steps: 4  // Optimized for 4 steps
  }
});
```

### Stable Diffusion Models

| Model | Endpoint | Best For |
|-------|----------|----------|
| Fast SDXL | `fal-ai/fast-sdxl` | Speed, lower cost |
| SDXL | `fal-ai/stable-diffusion-xl` | Classic SDXL |
| SD 1.5 | `fal-ai/stable-diffusion-v15` | Legacy compatibility |
| SDXL Turbo | `fal-ai/sdxl-turbo` | Ultra-fast |

```typescript
// Fast SDXL - Good balance of speed and quality
const result = await fal.subscribe("fal-ai/fast-sdxl", {
  input: {
    prompt: "A colorful abstract painting",
    image_size: "square_hd",
    num_inference_steps: 25
  }
});
```

### Specialized Image Models

| Model | Endpoint | Use Case |
|-------|----------|----------|
| Recraft V3 | `fal-ai/recraft-v3` | Design assets, vectors |
| Ideogram | `fal-ai/ideogram` | Text in images |
| Playground v2.5 | `fal-ai/playground-v25` | Creative/artistic |
| Kandinsky 3 | `fal-ai/kandinsky-3` | Russian model |

### Image-to-Image Models

| Model | Endpoint | Use Case |
|-------|----------|----------|
| FLUX i2i | `fal-ai/flux/dev/image-to-image` | Transform images |
| FLUX Inpaint | `fal-ai/flux/dev/inpainting` | Edit regions |
| FLUX ControlNet | `fal-ai/flux/dev/controlnet` | Guided generation |
| IP-Adapter | `fal-ai/ip-adapter-flux` | Style transfer |

```typescript
// Image-to-Image transformation
const result = await fal.subscribe("fal-ai/flux/dev/image-to-image", {
  input: {
    image_url: "https://example.com/photo.jpg",
    prompt: "Transform into watercolor painting style",
    strength: 0.75  // 0-1, how much to change
  }
});

// Inpainting (edit specific regions)
const result = await fal.subscribe("fal-ai/flux/dev/inpainting", {
  input: {
    image_url: "https://example.com/photo.jpg",
    mask_url: "https://example.com/mask.png",
    prompt: "A golden retriever"
  }
});

// ControlNet (structural guidance)
const result = await fal.subscribe("fal-ai/flux/dev/controlnet", {
  input: {
    prompt: "Modern house design",
    control_image_url: "https://example.com/edges.png",
    controlnet_conditioning_scale: 0.8
  }
});
```

## Video Generation Models

### Text-to-Video

| Model | Endpoint | Quality | Duration | Audio | Best For |
|-------|----------|---------|----------|-------|----------|
| Kling 2.6 Pro | `fal-ai/kling-video/v2.6/pro` | Highest | 5-10s | Native | Cinematic |
| Sora 2 | `fal-ai/sora` | Highest | 5-20s | Optional | Advanced |
| LTX-2 Pro | `fal-ai/ltx-video-2-pro` | High | 5s | Yes | Fast HQ |
| Runway Gen-3 | `fal-ai/runway/gen3/turbo` | High | 5-10s | No | Fast |
| Luma | `fal-ai/luma-dream-machine` | Good | 5s | No | Creative |
| CogVideoX | `fal-ai/cogvideox` | Good | 6s | No | Open source |

**Kling 2.6 Pro** - Best overall quality
```typescript
const result = await fal.subscribe("fal-ai/kling-video/v2.6/pro", {
  input: {
    prompt: "A majestic eagle soaring over mountains at golden hour",
    duration: 5,
    aspect_ratio: "16:9",
    negative_prompt: "blurry, distorted",
    cfg_scale: 0.5
  }
});
```

**LTX-2 Pro** - Fast with audio
```typescript
const result = await fal.subscribe("fal-ai/ltx-video-2-pro", {
  input: {
    prompt: "Ocean waves crashing on rocks",
    resolution: "720p",
    enable_audio: true
  }
});
```

### Image-to-Video

| Model | Endpoint | Best For |
|-------|----------|----------|
| MiniMax Hailuo | `fal-ai/minimax/video-01` | Image animation |
| Kling i2v | `fal-ai/kling-video/v2.6/pro/image-to-video` | HQ animation |
| Luma i2v | `fal-ai/luma-dream-machine` | Creative |
| Runway i2v | `fal-ai/runway/gen3/turbo/image-to-video` | Fast |

```typescript
// Animate a still image
const result = await fal.subscribe("fal-ai/minimax/video-01", {
  input: {
    image_url: "https://example.com/portrait.jpg",
    prompt: "Person slowly turns head and smiles",
    prompt_optimizer: true
  }
});
```

### Video-to-Video (Editing)

```typescript
// Edit/transform existing video
const result = await fal.subscribe("fal-ai/kling-video/o1", {
  input: {
    video_url: "https://example.com/video.mp4",
    prompt: "Change to anime style"
  }
});
```

## Audio Models

### Speech-to-Text

| Model | Endpoint | Best For |
|-------|----------|----------|
| Whisper | `fal-ai/whisper` | Accurate transcription |
| Whisper Turbo | `fal-ai/whisper-turbo` | Fast transcription |

```typescript
const result = await fal.subscribe("fal-ai/whisper", {
  input: {
    audio_url: "https://example.com/speech.mp3",
    task: "transcribe",  // or "translate"
    language: "en",
    chunk_level: "segment"
  }
});

console.log(result.text);
console.log(result.chunks);  // With timestamps
```

### Text-to-Speech

| Model | Endpoint | Best For |
|-------|----------|----------|
| Elevenlabs | `fal-ai/elevenlabs` | Premium voices |
| F5-TTS | `fal-ai/f5-tts` | Voice cloning |
| Kokoro | `fal-ai/kokoro` | Multi-language |

```typescript
// Text-to-speech with Elevenlabs
const result = await fal.subscribe("fal-ai/elevenlabs", {
  input: {
    text: "Hello, welcome to our service.",
    voice_id: "voice_id_here"
  }
});
```

## 3D Generation Models

| Model | Endpoint | Use Case |
|-------|----------|----------|
| TripoSR | `fal-ai/triposr` | Image to 3D mesh |
| InstantMesh | `fal-ai/instantmesh` | Fast 3D generation |
| Stable Zero123 | `fal-ai/stable-zero123` | Novel view synthesis |

```typescript
// Generate 3D mesh from image
const result = await fal.subscribe("fal-ai/triposr", {
  input: {
    image_url: "https://example.com/object.jpg"
  }
});

console.log(result.model_mesh.url);  // GLB/OBJ file
```

## Model Selection Decision Tree

```text
What do you want to create?
├── Image
│   ├── From text only?
│   │   ├── Need best quality? → FLUX.2 Pro
│   │   ├── Need fast iteration? → FLUX Schnell
│   │   ├── Need open-source? → FLUX.1 Dev
│   │   └── Budget conscious? → Fast SDXL
│   ├── Transform existing image?
│   │   ├── Style transfer → FLUX i2i
│   │   ├── Edit specific region → FLUX Inpainting
│   │   └── Follow structure → FLUX ControlNet
│   └── Need text in image? → Ideogram
│
├── Video
│   ├── From text only?
│   │   ├── Need best quality? → Kling 2.6 Pro
│   │   ├── Need fast preview? → Runway Gen-3 Turbo
│   │   └── Need audio? → LTX-2 Pro or Kling
│   ├── Animate image? → MiniMax Hailuo
│   └── Edit video? → Kling O1
│
├── Audio
│   ├── Speech to text?
│   │   ├── Accurate → Whisper
│   │   └── Fast → Whisper Turbo
│   └── Text to speech? → Elevenlabs / F5-TTS
│
└── 3D
    └── Image to 3D? → TripoSR
```

## Performance Comparison

### Image Generation Speed

| Model | ~Time (1024x1024) |
|-------|-------------------|
| FLUX Schnell | 1-2s |
| Fast SDXL | 2-3s |
| FLUX.1 Dev | 5-8s |
| FLUX.2 Pro | 8-12s |

### Video Generation Speed

| Model | ~Time (5s video) |
|-------|------------------|
| Runway Gen-3 Turbo | 30-60s |
| LTX-2 Pro | 60-90s |
| Kling 2.6 Pro | 120-180s |

## Cost Optimization Strategies

1. **Development Phase**
   - Use FLUX Schnell for prompt iteration
   - Use Fast SDXL for quick tests
   - Use Runway Gen-3 Turbo for video previews

2. **Production Phase**
   - FLUX.2 Pro for final images
   - Kling 2.6 Pro for final videos

3. **Batch Processing**
   - Process during off-peak hours
   - Use appropriate image sizes (don't upscale unnecessarily)
   - Cache results by seed for reproducibility

4. **Resource Efficiency**
   - Generate at target resolution (don't generate larger and downscale)
   - Use webhooks for high-volume (avoid polling overhead)
   - Implement client-side caching

## Model-Specific Tips

### FLUX Tips
- Guidance scale 3-4 works best
- 28 steps is optimal default
- Schnell works best with 4 steps only
- Detailed prompts produce better results

### Video Tips
- Include camera movement in prompts
- Describe action/motion explicitly
- Use negative prompts to avoid artifacts
- Start with shorter duration for testing

### Whisper Tips
- Provide language hint for better accuracy
- Use "translate" task for non-English to English
- chunk_level="segment" gives timestamps

## Explore More Models

Visit https://fal.ai/models for the complete catalog of 600+ models including:
- Face restoration/enhancement
- Background removal
- Upscaling
- Style transfer
- OCR
- Object detection
- And many more specialized models