Working with Models

OpenCauldron supports 27 models across 9 providers through a unified interface. Each model has different strengths — choose the right one for each job.

Selecting a model

Models are organized as cards in the generation interface. Some models have variants — shown as a segmented control on the card — that share the same provider but differ in speed, quality, or cost.

Each model card shows:

Cost per generation (per image or per second of video)
Average generation time
Supported features (audio, camera control, etc.)

Image models

Google (Imagen / Gemini)

Variant	Cost	Speed	Best for
Imagen 4	$0.04/img	~8s	Photorealistic, high-quality output
Imagen 4 Ultra	$0.08/img	~12s	Maximum quality, 2K resolution
Imagen 4 Fast	$0.02/img	~4s	Rapid iteration with good quality
Gemini Flash	$0.002/img	~3s	Fast and cheap, great for testing
Gemini Flash Lite	$0.001/img	~2s	Cheapest option, rapid prototyping

Key capabilities: negative prompt, seed, resolution (1K/2K or up to 4K on Gemini), person generation controls, watermark toggle, provider prompt enhance, output format.

Gemini Flash models support more aspect ratios (10 options) than Imagen 4 (5 options).

API key: GEMINI_API_KEY

Black Forest Labs (Flux)

Variant	Cost	Speed	Best for
Flux 1.1 Pro	$0.04/img	~6s	General purpose, high quality
Flux Dev	$0.025/img	~8s	Iteration with guidance/steps control
Flux Kontext Pro	$0.04/img	~8s	Image editing, character consistency, text rendering
Flux 2 Klein	$0.015/img	~2s	Budget drafts, sub-second inference

Key capabilities: seed, output format, prompt upsampling. Flux Dev adds guidance and steps sliders for fine control over the diffusion process.

API key: BFL_API_KEY

Ideogram

Variant	Cost	Speed	Best for
Ideogram 3	$0.06/img	~10s	Text rendering in images, wide style range

Key capabilities: 14 artistic styles, negative prompt, seed, rendering speed (Turbo/Default/Quality), batch generation (up to 8). Supports the most aspect ratios (11 options) of any image model.

API key: IDEOGRAM_API_KEY

Recraft

Variant	Cost	Speed	Best for
Recraft V3	$0.04/img	~8s	Design and illustration
Recraft 20B	$0.02/img	~5s	Budget design work
Recraft V4	$0.04/img	~8s	Improved quality, 10K char prompts
Recraft V4 Pro	$0.08/img	~10s	Premium, 4MP print-ready output

Key capabilities: 12 styles (realistic, vector, icon, digital illustration, and sub-styles), negative prompt, CFG scale, batch generation (up to 6).

API key: RECRAFT_API_KEY

xAI (Grok)

Variant	Cost	Speed	Best for
Grok Imagine	$0.02/img	~5s	Fast, creative generation
Grok Imagine Pro	$0.07/img	~8s	Highest quality, up to 2K

Key capabilities: resolution (1K/2K), batch generation (up to 10). Note: does not support negative prompts.

API key: XAI_API_KEY

Video models

Google (Veo)

Variant	Cost	Speed	Best for
Veo 3	$0.15/s	~120s	Native audio, high quality
Veo 3.1	$0.15/s	~120s	4K support, video extension up to 148s
Veo 3 Fast	$0.08/s	~60s	Same quality, lower latency

Key capabilities: native audio generation, image-to-video, resolution (720p/1080p/4K), negative prompt, seed, person generation controls. Durations: 5–8s.

API key: GEMINI_API_KEY

Runway

Variant	Cost	Speed	Best for
Gen-4 Turbo	$0.05/s	~30s	Cinematic video, fast turnaround
Gen-4.5	$0.10/s	~45s	Flagship text + image to video

Key capabilities: image-to-video, seed, resolution (720p/1080p). Durations: 5s or 10s.

API key: RUNWAY_API_KEY

Kling (via fal.ai)

Variant	Cost	Speed	Best for
Kling 2.1	$0.075/s	~90s	Top-tier motion quality
Kling 2.1 Pro	$0.15/s	~90s	Higher quality, motion brush

Key capabilities: negative prompt, CFG scale, image-to-video, resolution (720p/1080p). Durations: 5s or 10s.

API key: FAL_KEY

Hailuo (MiniMax)

Variant	Cost	Speed	Best for
Hailuo 2.3	$0.045/s	~60s	Best cost/quality ratio, native audio
Hailuo 2.3 Fast	$0.03/s	~30s	Faster iteration, cheaper

Key capabilities: native audio, image-to-video, prompt optimizer, resolution (720p/1080p). Durations: 6s or 10s.

API key: MINIMAX_API_KEY

Luma (Ray)

Variant	Cost	Speed	Best for
Ray 2	$0.07/s	~60s	Camera controls, extendable to 60s
Ray Flash 2	$0.025/s	~20s	3x faster, up to 15s duration

Key capabilities: camera motion controls (pan, zoom, orbit), loop video, image-to-video, resolution (540p–4K), most aspect ratio options of any video model (7 options). Durations: 5–10s.

API key: LUMA_API_KEY

Cost comparison

Image models (per image)

Model	Cost
Gemini Flash Lite	$0.001
Gemini Flash	$0.002
Flux 2 Klein	$0.015
Recraft 20B	$0.02
Grok Imagine	$0.02
Imagen 4 Fast	$0.02
Flux Dev	$0.025
Flux 1.1 Pro	$0.04
Flux Kontext Pro	$0.04
Imagen 4	$0.04
Recraft V3 / V4	$0.04
Ideogram 3	$0.06
Grok Imagine Pro	$0.07
Imagen 4 Ultra	$0.08
Recraft V4 Pro	$0.08

Video models (per second)

Model	Cost
Ray Flash 2	$0.025
Hailuo 2.3 Fast	$0.03
Hailuo 2.3	$0.045
Runway Gen-4 Turbo	$0.05
Ray 2	$0.07
Kling 2.1	$0.075
Veo 3 Fast	$0.08
Runway Gen-4.5	$0.10
Kling 2.1 Pro	$0.15
Veo 3 / 3.1	$0.15

Configuring providers

Each provider requires its own API key set as an environment variable. Only models with configured keys appear in the interface. See the Configuration guide for details on setting environment variables.

For details on what each parameter does, see the Generation Parameters reference.