TL;DR: FLUX is the better generator out of the box — it follows complex prompts, renders readable text and gets hands right more often, at roughly $0.03–$0.06 per image through an API. Stable Diffusion is the better platform: it is free to run on your own hardware, and its ecosystem of thousands of fine-tuned models and LoRAs can produce styles FLUX simply cannot. Choose FLUX for reliable results today; choose Stable Diffusion for control, privacy and zero per-image cost.
Research-based comparison. Prices checked October 2026. We do not claim hands-on testing. Featured illustration is illustrative artwork, not a product screenshot.
FLUX vs Stable Diffusion at a glance
| Feature | FLUX (Black Forest Labs) | Stable Diffusion (Stability AI) | Edge |
|---|---|---|---|
| Cost | API about $0.03–$0.06/image (Pro); Schnell about $0.003 via partners | Free locally; API about $0.02–$0.04/image | SD locally, FLUX by API |
| Prompt adherence | Excellent — follows complex scenes closely | Good; varies by checkpoint | FLUX |
| Text in images | Strong, often readable | Weaker on base models | FLUX |
| Hands and anatomy | Fewer errors out of the box | More fixing and inpainting | FLUX |
| Custom styles | Growing fine-tune support | Thousands of checkpoints and LoRAs | Stable Diffusion |
| Hardware | Open variants are heavy; most use the API | SD 3.5 Medium runs at about 10GB VRAM; older SD 1.5 at 4GB | Stable Diffusion |
| Setup effort | Sign up, call the API | Install, manage models and settings | FLUX |
| Licensing | Varies by variant — check before commercial use | Community licence for SD 3.5 family | Read the fine print |
What FLUX does better
FLUX, from Black Forest Labs — a team with roots in the original Stable Diffusion research — wins the first-generation test. Describe a complicated scene with several objects, a sign with real words and a person holding something, and FLUX is far more likely to deliver it in one or two tries, with text that actually reads and hands that mostly behave. For product teams that math matters: at about $0.03 to $0.06 per image for the Pro model through partner APIs (and far less for the fast Schnell variant), a high first-try success rate beats a cheaper model you have to re-roll five times. The catch is licensing and weight: the variants differ, the best-quality route is a hosted API, and running the big open variants locally takes serious VRAM.
What Stable Diffusion does better
Stable Diffusion wins the second year of any project. Because the weights are open, the community has built thousands of specialised checkpoints and LoRAs — a particular illustrator’s style, a consistent character, a niche product category — plus mature tools like ControlNet for pose and composition control. Running locally means no per-image bill, no queue and no prompts leaving your machine, which matters for client work under NDA. SD 3.5 Medium runs on consumer hardware at around 10GB of VRAM, and the older SD 1.5 ecosystem still runs on 4GB. The price is your time: installation, model management and more inpainting to fix anatomy than FLUX usually needs.
Which should you pick?
Pick FLUX if you need dependable, prompt-accurate images through an API — marketing assets, product visuals, anything with text in it — and you would rather pay cents per image than maintain infrastructure. Pick Stable Diffusion if you generate at high volume, need a specific fine-tuned style or character consistency, work with sensitive material, or already own a decent GPU. Many working creators use both: FLUX for fast, accurate drafts and client-safe output, Stable Diffusion for the specialised styles only its ecosystem has.
FAQ
Is Stable Diffusion really free?
Yes to run locally — the cost is your hardware and electricity. Hosted APIs charge roughly $0.02–$0.04 per image.
How much does FLUX cost?
Through partner APIs, roughly $0.03–$0.06 per image for FLUX Pro and around $0.003 for the fast Schnell variant. Prices vary by provider.
Which is better for text in images?
FLUX, clearly. It is one of the few model families that renders short text legibly without heavy post-processing.
Can FLUX run on my own computer?
The open variants can, but they are heavy. Most people use FLUX through an API and run Stable Diffusion locally instead.
Bottom line: FLUX is the better camera; Stable Diffusion is the better darkroom. Rent the camera until your volume or style needs justify building the darkroom.