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FLUX.2 Provs.Stable Diffusion 3.5 Medium

Which one is better?

In our own test, FLUX.2 Pro leads. Stable Diffusion 3.5 Medium has no arena rating yet. Stable Diffusion 3.5 Medium has no API price.

Same prompt, two images

Same task, the first image of each. The task with the biggest difference is preselected.

FLUX.2 Pro: Character and detail, first image from the fixed test run
FLUX.2 Pro85 out of 100
Stable Diffusion 3.5 Medium: Character and detail, first image from the fixed test run
Stable Diffusion 3.5 Medium16 out of 100

Result for “Character and detail”:FLUX.2 Pro ahead

Prompt given to both modelsCreate a square cinematic full-body portrait of a fictional bicycle courier waiting under a transparent umbrella at a rainy tram stop in Hamburg at blue hour. She wears a mustard raincoat, navy trousers, red sneakers, a silver helmet, and carries a teal messenger bag. Keep both hands visible, render the bicycle correctly, use realistic wet-street reflections, and include no readable brand names.

What the rating looks at: Anatomy, clothing, and spatial consistency.

“Ahead”: better in all three rating rounds. “Slightly ahead”: a higher value, but not in every round.

Test protocol of the images

Both models receive the same archived prompt in exactly one request, and the first result counts. Files are normalized to 1,024 × 1,024 pixels without cropping. Provider resolution, randomness, quality tier and prompt processing can still differ. The images are a practical visual test, not a reconstruction of the arena configuration.

Character and detail

FLUX.2 Pro: together, 1024x1024, n=1, seed=provider random, provider default steps, generated Aug 14, 2026, 12:30 PM. Source

Stable Diffusion 3.5 Medium: fal, requested 1024x1024, n=1, seed=provider random, estimated cost $0.020000, generated Nov 1, 2026, 9:17 PM. Source

Protocol gradually-image-comparison-v1. Prompt SHA 256: 985a75b38642a9f0e5e0c0e0c67f1b7f67780d42bd2168fa24e9a7a7a94b0da6

FLUX.2 Pro image SHA 256: 9eec1a6900b6031703d2e797b93c2aba6c5f45b4807b560a0bf1e37eac9e20f2

Stable Diffusion 3.5 Medium image SHA 256: 6b8aa732e94479ad302904096c5031908141e4083ee099f080185aa04c2ea800

Infographic

FLUX.2 Pro: together, 1024x1024, n=1, seed=provider random, provider default steps, generated Aug 14, 2026, 12:31 PM. Source

Stable Diffusion 3.5 Medium: fal, requested 1024x1024, n=1, seed=provider random, estimated cost $0.020000, generated Nov 1, 2026, 9:17 PM. Source

Protocol gradually-image-comparison-v1. Prompt SHA 256: ed65cb4e6a51e2336f8b149ad4cbb16e020f07d527ad94362e719d2dcf91d94f

FLUX.2 Pro image SHA 256: ea47f772cdfa26bf21528ae7e09d245eb7a3be7d3185af15cedd7d21acdfbb09

Stable Diffusion 3.5 Medium image SHA 256: 61b12e227431387098e51c6ce6d059be9d8df9c85263b994bee62602e2ddfd16

Product photography

FLUX.2 Pro: together, 1024x1024, n=1, seed=provider random, provider default steps, generated Aug 14, 2026, 12:30 PM. Source

Stable Diffusion 3.5 Medium: fal, requested 1024x1024, n=1, seed=provider random, estimated cost $0.020000, generated Nov 1, 2026, 9:16 PM. Source

Protocol gradually-image-comparison-v1. Prompt SHA 256: c67fd71e91304458a2feef5c91efa8677260fab0c0099a29a2c52cb579f5b2f3

FLUX.2 Pro image SHA 256: 4d9b922f59b329c5ac3532222c8e340e7fdcb1920ce6f03ad9299f25a6beec43

Stable Diffusion 3.5 Medium image SHA 256: 2412a20e61c118ce7ab7ff83e285b96eb32d5c0f1171cc769e153db6655b8f67

Typography and layout

FLUX.2 Pro: together, 1024x1024, n=1, seed=provider random, provider default steps, generated Aug 14, 2026, 2:02 PM. Source

Stable Diffusion 3.5 Medium: fal, requested 1024x1024, n=1, seed=provider random, estimated cost $0.020000, generated Nov 1, 2026, 9:16 PM. Source

Protocol gradually-image-comparison-v1. Prompt SHA 256: 2e012c3d14ee5dd02203a94f394ca80a5038cdebd6032b25a8b8a221f2255419

FLUX.2 Pro image SHA 256: 5a5d8ccd657d7522bc39fdec4b0aecf198b42c282a5aefde9461239dfe5c0396

Stable Diffusion 3.5 Medium image SHA 256: bc854c3269ea8bada6f764545f4a09abedc110219018c09f2fa5708a14d9af7e

The numbers at a glance

Arena ratingfrom votes by users · higher is better
1,153

FLUX.2 Pro

Rank 18 of 22

n/a

Stable Diffusion 3.5 Medium

not in the arena

GraduallyBenchour own rating, 0 to 100 · higher is better
60

FLUX.2 Pro

Rank 29 of 74

16

Stable Diffusion 3.5 Medium

Rank 69 of 74

Price per imagedollars through the API · lower is better
$0.03

FLUX.2 Pro

cheap

n/a

Stable Diffusion 3.5 Medium

no API price

Ranks among the 22 image models with an arena rating and the 74 with a GraduallyBench run; prices compared with 28 models with an API price.

FLUX.2 Pro

Subscription
No Black Forest Labs subscription includes this model. Through other providers from ≈ €6.39 a month (ElevenLabs Starter, with limited credits). 43 plans in Germany.
Via API
$0.03 per image, 100 images $3.

Stable Diffusion 3.5 Medium

Subscription
n/a No plan in Germany names exactly this model.
Via API
No API price known. Access: API, local.
License
Open weights.

Subscriptions only count plans that name exactly this model. Subscription prices include VAT, API prices are in dollars.

Arena rating (LMArena) from Oct 28, 2026 · GraduallyBench from Nov 1, 2026 · API prices from Oct 28, 2026 · Subscription database from Sep 29, 2026 (34 days old)

All data side by side

The better value is bold. For ratings only when the gap is clear.

KennzahlFLUX.2 ProStable Diffusion 3.5 Medium
Ratings
Arena ratingfrom votes by users, higher is better1,153n/a
Arena rankRank 18 of 22n/a
Arena votesmore votes, a safer rating223,179n/a
GraduallyBenchour own rating, 0 to 1006016
GraduallyBench by task
Typography and layoutLegible text, hierarchy, and composition7117
Product photographyMaterials, reflections, and fine details4713
Character and detailAnatomy, clothing, and spatial consistency8516
InfographicNumbers, labels, and visual organization3720
API price
Per imagelower is better$0.03n/a
100 images$3n/a
Profile
ReleasedNovember 2025Oct 29, 2024
Weightsopen means: runs locallyproprietaryopen
AccessAPI, Web appAPI, local
Parametersnot published2.5 billion
Largest output4 Megapixelnot consistently published
Plans in Germanynaming exactly this model43n/a

API prices for one image at 1,024 × 1,024 pixels according to Artificial Analysis.

Sources: FLUX.2 Pro model source (verified Sep 24, 2026) · Stable Diffusion 3.5 Medium model source (verified Nov 1, 2026)

Arena ratings by category

From blind votes on LMArena. “Ahead” means the lead is clear.

No shared arena score in the stored snapshot

The stored benchmark database contains no measurement for FLUX.2 Pro and Stable Diffusion 3.5 Medium from the same arena and category. Older model versions are not used as substitutes.

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