fal.ai - Serverless AI Platform
Generate images, videos, and audio with fal.ai's fast serverless inference.
Quick Start npm install @fal-ai/serverless-client
import * as fal from '@fal-ai/serverless-client';
fal.config({ credentials: process.env.FAL_KEY, });
// Generate image with Flux const result = await fal.subscribe('fal-ai/flux/dev', { input: { prompt: 'A serene Japanese garden with cherry blossoms', image_size: 'landscape_16_9', num_images: 1, }, });
console.log(result.images[0].url);
Authentication // Option 1: Environment variable (recommended) // Set FAL_KEY in .env fal.config({ credentials: process.env.FAL_KEY });
// Option 2: Direct config fal.config({ credentials: 'your-api-key' });
// Option 3: Proxy (for client-side apps) // Use fal.config({ proxyUrl: '/api/fal/proxy' }) on client
Image Generation Models Flux (Fastest, High Quality) // Flux Dev - Best quality const result = await fal.subscribe('fal-ai/flux/dev', { input: { prompt: 'Professional headshot of a business executive', image_size: 'square_hd', // 1024x1024 num_inference_steps: 28, guidance_scale: 3.5, num_images: 1, enable_safety_checker: true, }, });
// Flux Schnell - Ultra fast (~0.5s) const fast = await fal.subscribe('fal-ai/flux/schnell', { input: { prompt: 'A cute robot', image_size: 'square', num_inference_steps: 4, // Schnell needs fewer steps }, });
// Flux Pro - Highest quality const pro = await fal.subscribe('fal-ai/flux-pro', { input: { prompt: 'Hyperrealistic portrait', image_size: 'portrait_4_3', safety_tolerance: '2', }, });
Image Sizes type ImageSize = | 'square_hd' // 1024x1024 | 'square' // 512x512 | 'portrait_4_3' // 768x1024 | 'portrait_16_9' // 576x1024 | 'landscape_4_3' // 1024x768 | 'landscape_16_9' // 1024x576 | { width: number; height: number }; // Custom
SDXL & Stable Diffusion // SDXL const sdxl = await fal.subscribe('fal-ai/fast-sdxl', { input: { prompt: 'Fantasy landscape', negative_prompt: 'blurry, low quality', image_size: 'landscape_16_9', num_inference_steps: 25, guidance_scale: 7.5, scheduler: 'DPM++ 2M Karras', }, });
// Stable Diffusion 3 const sd3 = await fal.subscribe('fal-ai/stable-diffusion-v3-medium', { input: { prompt: 'A mountain lake at sunset', negative_prompt: 'ugly, deformed', image_size: 'landscape_16_9', }, });
Image-to-Image Image Editing with Flux // Image to image const result = await fal.subscribe('fal-ai/flux/dev/image-to-image', { input: { prompt: 'Transform to watercolor painting style', image_url: 'https://example.com/photo.jpg', strength: 0.75, // How much to change (0-1) num_inference_steps: 28, }, });
// Inpainting (edit specific areas) const inpaint = await fal.subscribe('fal-ai/flux/dev/inpainting', { input: { prompt: 'A red sports car', image_url: 'https://example.com/street.jpg', mask_url: 'https://example.com/mask.png', // White = edit area }, });
ControlNet // Generate with pose/edge control const controlled = await fal.subscribe('fal-ai/flux-controlnet', { input: { prompt: 'A professional dancer', control_image_url: 'https://example.com/pose.jpg', controlnet_conditioning_scale: 0.8, }, });
Video Generation Kling Video const video = await fal.subscribe('fal-ai/kling-video/v1/standard/text-to-video', { input: { prompt: 'A golden retriever running through a field of flowers', duration: '5', // seconds aspect_ratio: '16:9', }, });
console.log(video.video.url);
Image to Video const i2v = await fal.subscribe('fal-ai/kling-video/v1/standard/image-to-video', { input: { prompt: 'The person starts walking forward', image_url: 'https://example.com/person.jpg', duration: '5', }, });
Luma Dream Machine const luma = await fal.subscribe('fal-ai/luma-dream-machine', { input: { prompt: 'A timelapse of clouds moving over mountains', aspect_ratio: '16:9', }, });
Real-Time Generation WebSocket Streaming import * as fal from '@fal-ai/serverless-client';
// Real-time image generation with streaming const stream = await fal.stream('fal-ai/flux/dev', { input: { prompt: 'A beautiful sunset', image_size: 'landscape_16_9', }, });
for await (const event of stream) { if (event.images) { console.log('Generated:', event.images[0].url); } }
Real-Time SDXL (Low Latency) // Ultra-low latency for interactive apps const realtime = await fal.subscribe('fal-ai/fast-lcm-diffusion', { input: { prompt: 'Abstract art', image_size: 'square', num_inference_steps: 4, // LCM needs very few steps }, });
Background Removal & Editing // Remove background const nobg = await fal.subscribe('fal-ai/birefnet', { input: { image_url: 'https://example.com/photo.jpg', }, });
// Upscale image const upscaled = await fal.subscribe('fal-ai/creative-upscaler', { input: { image_url: 'https://example.com/small.jpg', scale: 2, creativity: 0.5, prompt: 'High quality, detailed', }, });
// Face swap const swapped = await fal.subscribe('fal-ai/face-swap', { input: { base_image_url: 'https://example.com/target.jpg', swap_image_url: 'https://example.com/face.jpg', }, });
Next.js Integration API Route (App Router) // app/api/generate/route.ts import * as fal from '@fal-ai/serverless-client'; import { NextRequest, NextResponse } from 'next/server';
fal.config({ credentials: process.env.FAL_KEY });
export async function POST(request: NextRequest) { const { prompt, model = 'fal-ai/flux/schnell' } = await request.json();
try { const result = await fal.subscribe(model, { input: { prompt, image_size: 'landscape_16_9', num_images: 1, }, });
return NextResponse.json({
imageUrl: result.images[0].url,
seed: result.seed,
});
} catch (error) { return NextResponse.json({ error: 'Generation failed' }, { status: 500 }); } }
Proxy Route for Client-Side // app/api/fal/proxy/route.ts import { route } from '@fal-ai/serverless-client/server-proxy';
export const { GET, POST, PUT, DELETE } = route;
// Client-side usage 'use client'; import * as fal from '@fal-ai/serverless-client';
fal.config({ proxyUrl: '/api/fal/proxy' });
async function generateImage(prompt: string) { const result = await fal.subscribe('fal-ai/flux/schnell', { input: { prompt, image_size: 'square_hd' }, }); return result.images[0].url; }
Queue System for Long Tasks // Submit to queue (returns immediately) const { request_id } = await fal.queue.submit('fal-ai/flux/dev', { input: { prompt: 'Complex scene', num_images: 4 }, });
// Check status const status = await fal.queue.status('fal-ai/flux/dev', { requestId: request_id, }); console.log(status.status); // 'IN_QUEUE' | 'IN_PROGRESS' | 'COMPLETED'
// Get result when ready if (status.status === 'COMPLETED') { const result = await fal.queue.result('fal-ai/flux/dev', { requestId: request_id, }); }
// Or use webhooks await fal.queue.submit('fal-ai/flux/dev', { input: { prompt: 'Scene' }, webhookUrl: 'https://your-server.com/webhook', });
Model Comparison Model Speed Quality Best For flux/schnell ~0.5s Good Real-time, previews flux/dev ~3s Excellent Production images flux-pro ~5s Best Professional work fast-sdxl ~2s Good General purpose sd-v3-medium ~4s Excellent Detailed scenes kling-video ~60s Good Video generation Resources fal.ai Docs: https://fal.ai/docs Model Gallery: https://fal.ai/models API Reference: https://fal.ai/docs/api-reference Pricing: https://fal.ai/pricing