Which image model is the fastest?

Turbo and lightning variants — SDXL Turbo, FLUX Schnell, Ideogram Turbo — render a 1024px image in 1-3 seconds. Standard flagship pipelines (FLUX Pro, Imagen 3) take 6-15 seconds. Pick the turbo tier when you're previewing in a UI and the flagship when the image is final.

Which model is best for photorealism?

FLUX 1.1 Pro and Imagen 3 currently lead on skin texture, lighting realism, and hand anatomy. Recraft V3 wins on product photography and white-background commerce shots. For full photoreal portraits, FLUX 1.1 Pro Ultra adds another step of detail at roughly twice the cost.

Is pricing per-image or per-token?

Image generation is billed per-call. A standard 1024×1024 image is one call. Higher resolutions, more diffusion steps, and edit operations may multiply the price — check the model card for the exact rate.

What resolutions are supported?

Standard tiers ship 1024×1024 and common aspect ratios (1:1, 16:9, 9:16, 4:3, 3:4). Pro tiers add 2K and 4K outputs and arbitrary aspect ratios up to 2048 on the long edge. Upscalers in the image-edit category push results to 4K and beyond.

Can I edit existing images?

Yes — inpainting, outpainting, controlled edits via mask + prompt, and reference-image conditioning are all supported. The /models/image-edit page lists models specifically tuned for editing, including FLUX Fill, FLUX Canny, FLUX Depth, and IP-Adapter variants.

Can I control the style?

Three ways: (1) prompt-engineering with style references ('in the style of...'), (2) LoRAs or style adapters where supported, and (3) IP-Adapter and FLUX Redux for image-to-image style transfer. Recraft V3 and Ideogram offer named style presets directly in the API.

Can I use generated images commercially?

Almost always yes. Every commercial-tier model on Railwail grants a perpetual, royalty-free commercial-use license. A few open-weights checkpoints (mostly research previews) restrict to non-commercial — the model card lists the license explicitly so you know before you ship.

Is there a speed vs quality knob I can tune?

Yes: most diffusion models expose a `num_inference_steps` (or equivalent) parameter. Default is usually 20-30 steps for a good balance. Drop to 4-8 steps with a turbo variant for instant previews; bump to 50+ steps on a Pro tier for final renders. Quality plateaus around step 50 for most models.

Image Generation

Create stunning visuals with state-of-the-art AI models

Image generation models for product, marketing, and design

Image models turn a text prompt — and optionally a reference image or a mask — into a finished raster. The category covers everything from photoreal product shots to vector-style illustrations to controllable inpainting and outpainting. You reach for an image model when you need on-brand visuals at scale, when a designer's queue is the bottleneck, or when you want to ship a generative feature inside your own product.

Unlike text models, image generation is billed per-call rather than per-token. A single 1024×1024 image costs anywhere from half a cent (open-weights SDXL turbo) to fifteen cents (flagship Imagen or FLUX Pro). Higher resolutions and longer step counts cost proportionally more. Some providers expose a separate edit endpoint at a different rate; check the model card before integrating.

The core trade-off is photorealism versus controllability. Diffusion flagships (FLUX 1.1 Pro, Imagen 3, Recraft V3) produce magazine-quality output but ignore detailed compositional instructions about half the time. Smaller models (SDXL, Playground V3, Stable Diffusion 3.5) cost ten times less, render in under two seconds, and let you steer the result with ControlNet, IP-Adapter, or LoRA. For batch production work, the smaller and steerable pipeline almost always wins; for one-off hero shots, reach for the flagship.

Watch out for context dilution in image prompts: most diffusion models cap useful prompt length around 75 tokens, so jamming in twelve adjectives and three style references typically averages them all out instead of stacking them. Write the subject, the action, and the lighting first; everything after the third clause has diminishing influence on the result.

Licensing matters: most providers grant a perpetual commercial-use license on generated images, but a few (FLUX Schnell free tier, some open checkpoints) restrict to non-commercial. The model card spells it out — read it before you put output on a billboard.

Top picks below cover the photorealism flagship, the cheapest workhorse, the longest-prompt model, and the fastest realtime option in the category.