FLUX.2 Klein 9Bvs.Stable Diffusion 3.5 Large

Which one is better?

In our own test both are on par. In the arena, FLUX.2 Klein 9B leads. Both are in the lower half there, though. Stable Diffusion 3.5 Large has no API price.

Test images

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

FLUX.2 Klein 9B: Product photography, first image from the fixed test run — FLUX.2 Klein 9B87 out of 100

Stable Diffusion 3.5 Large: Product photography, first image from the fixed test run — Stable Diffusion 3.5 Large17 out of 100

Result for “Product photography”:FLUX.2 Klein 9B ahead

Prompt given to both modelsCreate a square premium product photograph of a brushed titanium wristwatch standing upright on dark green marble. The watch has a cream dial, thin black hands set to 10:10, twelve distinct hour markers, a realistic crown, and a dark brown leather strap. Soft window light from the left, controlled reflections, shallow depth of field, no text, no logo, no extra objects.

What the rating looks at: Materials, reflections, and fine details.

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

Test protocol of the images

Each test attempt uses the same archived prompt and one request. The first output of that attempt counts. Repeats after technical test failures are disclosed for the affected images. 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 Klein 9B: fal, requested 1024x1024, n=1, seed=1587849924, estimated cost $0.006291, generated Aug 14, 2026, 1:52 PM. Source

Stable Diffusion 3.5 Large: fal, requested 1024x1024, n=1, seed=7087247023770270000, estimated cost $0.068157, generated Aug 14, 2026, 2:37 PM. Source

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

FLUX.2 Klein 9B image SHA 256: 84eceab680e59de6b9d4e68b3c21f6515ce093ff7d110992049e847570dd565f

Stable Diffusion 3.5 Large image SHA 256: e748006fe56e442ad347e3f994f18b86ee1739f20dcee063aa7a03ee710c5d54

Infographic

FLUX.2 Klein 9B: fal, requested 1024x1024, n=1, seed=1082231541, estimated cost $0.006291, generated Aug 14, 2026, 1:52 PM. Source

Stable Diffusion 3.5 Large: fal, requested 1024x1024, n=1, seed=12166653711354006000, estimated cost $0.068157, generated Aug 14, 2026, 2:37 PM. Source

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

FLUX.2 Klein 9B image SHA 256: 1d2eb263ca5a25794a88df7bb04f5c13e10ed9a289371d1dcc7ed6d6e0a297e2

Stable Diffusion 3.5 Large image SHA 256: 4eb0fd741ef42e6d3fee4b1280cdfb098a0a04009b139051963895892e349f1e

Product photography

FLUX.2 Klein 9B: fal, requested 1024x1024, n=1, seed=1388538280, estimated cost $0.006291, generated Aug 14, 2026, 1:39 PM. Source

Stable Diffusion 3.5 Large: fal, requested 1024x1024, n=1, seed=13346308312015933000, estimated cost $0.068157, generated Aug 14, 2026, 2:37 PM. Source

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

FLUX.2 Klein 9B image SHA 256: e7208f19ccfb9b810b9648cb1861797b7155ad91933d1660059236cef413ebe0

Stable Diffusion 3.5 Large image SHA 256: ea9a7401dee8859ec2cb96af9f7ca29a177ef2202f52f629d8ce9f5839bd4061

Typography and layout

FLUX.2 Klein 9B: fal, requested 1024x1024, n=1, seed=1340991019, estimated cost $0.006291, generated Aug 14, 2026, 2:41 PM. Source

Stable Diffusion 3.5 Large: fal, requested 1024x1024, n=1, seed=16632333557910893000, estimated cost $0.068157, generated Aug 14, 2026, 2:37 PM. Source

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

FLUX.2 Klein 9B image SHA 256: c5f23870e70f2245d24a3689f2579ceb770e5edf8c3c89b7d6ed7ae138f262f6

Stable Diffusion 3.5 Large image SHA 256: e2994b1883a245b1c8c447957d121ea89d93aafff149029aa4e8507dbb769f9a

The numbers at a glance

Arena ratingfrom votes by users · higher is better

1,070

FLUX.2 Klein 9B

Rank 20 of 21

938

Stable Diffusion 3.5 Large

Rank 21 of 21

GraduallyBenchour own rating, 0 to 100 · higher is better

FLUX.2 Klein 9B

Rank 62 of 108

Stable Diffusion 3.5 Large

Rank 87 of 108

Price per imagedollars through the API · lower is better

$0.015

FLUX.2 Klein 9B

cheap

n/a

Stable Diffusion 3.5 Large

no API price

Ranks among the 21 image models with an arena rating and the 108 with a GraduallyBench run; prices compared with 28 models with an API price.

FLUX.2 Klein 9B

Subscription: n/a No plan in Germany names exactly this model.
Via API: $0.015 per image, 100 images $1.50.
License: Open weights, Weights released under the FLUX Non-Commercial License.

Stable Diffusion 3.5 Large

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 Nov 6, 2026 · GraduallyBench from Nov 3, 2026 · API prices from Nov 6, 2026 · Subscription database from Sep 29, 2026 (38 days old)

All data side by side

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

Kennzahl	FLUX.2 Klein 9B	Stable Diffusion 3.5 Large
Ratings
Arena ratingfrom votes by users, higher is better	1,070	938
Arena rank	Rank 20 of 21	Rank 21 of 21
Arena votesmore votes, a safer rating	150,686	23,396
GraduallyBenchour own rating, 0 to 100	50	27
GraduallyBench by task
Typography and layoutLegible text, hierarchy, and composition	32	31
Product photographyMaterials, reflections, and fine details	87	17
Character and detailAnatomy, clothing, and spatial consistency	39	23
InfographicNumbers, labels, and visual organization	42	39
API price
Per imagelower is better	$0.015	n/a
100 images	$1.50	n/a
Profile
Released	January 2026	Oct 22, 2024
Weightsopen means: runs locally	openWeights released under the FLUX Non-Commercial License	open
Access	API, local	API, local
Parameters	9 billion	8.1 billion
Largest output	4 Megapixel	1 Megapixel
Plans in Germanynaming exactly this model	n/a	n/a

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

Sources: FLUX.2 Klein 9B model source, status source (verified Sep 24, 2026) · Stable Diffusion 3.5 Large model source (verified Aug 15, 2026)

Arena ratings by category

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

Arena rating per categoryfrom votes by users · higher is betterFLUX.2 Klein 9BStable Diffusion 3.5 Large

Text to Image: 3D modeling1,079963ahead

Text to Image: Art1,079997ahead

Text to Image: Cartoon1,064945ahead

Text to Image: Commercial design1,070937ahead

Text to Image: Overall1,070938ahead

Text to Image: Photorealism1,091928ahead

Text to Image: Portraits1,092942ahead

Text to Image: Text rendering1,058921ahead

LMArena from Nov 6, 2026

All individual values with sources

Rating	FLUX.2 Klein 9B	Stable Diffusion 3.5 Large	Source
Text to Image: 3D modeling	1,079	963	LMArenaRetrieved Nov 6, 2026
Text to Image: Art	1,079	997	LMArenaRetrieved Nov 6, 2026
Text to Image: Cartoon	1,064	945	LMArenaRetrieved Nov 6, 2026
Text to Image: Commercial design	1,070	937	LMArenaRetrieved Nov 6, 2026
Text to Image: Overall	1,070	938	LMArenaRetrieved Nov 6, 2026
Text to Image: Photorealism	1,091	928	LMArenaRetrieved Nov 6, 2026
Text to Image: Portraits	1,092	942	LMArenaRetrieved Nov 6, 2026
Text to Image: Text rendering	1,058	921	LMArenaRetrieved Nov 6, 2026

Published specialist tests

This pair shares 7 results from published research benchmarks.

Specialist testspublished research benchmarks · higher is betterFLUX.2 Klein 9BStable Diffusion 3.5 Large

WISE Verified overall44%40%level

WISE culture49%49%level

WISE time39%41%level

WISE space55%44%ahead

WISE biology38%30%ahead

WISE physics48%38%ahead

WISE chemistry23%21%level

WISE Verified from Aug 26, 2026

All individual values with sources

Rating	FLUX.2 Klein 9B	Stable Diffusion 3.5 Large	Source
WISE Verified overall	44%	40%	WISE VerifiedRetrieved Aug 26, 2026
WISE culture	49%	49%	WISE VerifiedRetrieved Aug 26, 2026
WISE time	39%	41%	WISE VerifiedRetrieved Aug 26, 2026
WISE space	55%	44%	WISE VerifiedRetrieved Aug 26, 2026
WISE biology	38%	30%	WISE VerifiedRetrieved Aug 26, 2026
WISE physics	48%	38%	WISE VerifiedRetrieved Aug 26, 2026
WISE chemistry	23%	21%	WISE VerifiedRetrieved Aug 26, 2026

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Test images

The numbers at a glance

FLUX.2 Klein 9B

Stable Diffusion 3.5 Large

All data side by side

Arena ratings by category

Published specialist tests

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