FLUX.2 Klein 9B Previewvs.Sana-Sprint 0.6B 1024px

Which one is better?

In our own test, FLUX.2 Klein 9B Preview leads. Neither is in the arena. Neither has an API price.

Test images

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

FLUX.2 Klein 9B Preview: Infographic, first image from the fixed test run — FLUX.2 Klein 9B Preview75 out of 100

Sana-Sprint 0.6B 1024px: Infographic, first image from the fixed test run — Sana-Sprint 0.6B 1024px7 out of 100

Result for “Infographic”:FLUX.2 Klein 9B Preview ahead

Prompt given to both modelsCreate a square German infographic titled SO FUNKTIONIERT PHOTOSYNTHESE. Show exactly four numbered steps in this order: 1 LICHT, 2 WASSER, 3 CO₂, 4 ZUCKER + SAUERSTOFF. Use a clean editorial science style with one plant cross-section, simple arrows, high contrast, legible labels, and no other text.

What the rating looks at: Numbers, labels, and visual organization.

“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 Preview: manual, BFL API /v1/flux-2-klein-9b-preview (distinct preview checkpoint); native 1024x1024, 1:1; one request, first output; seed=3453819885; output_format=png; no reference images or negative prompt, generated Nov 2, 2026, 7:05 PM. Source

Sana-Sprint 0.6B 1024px: manual, 1:1, one request, first output, one image, provider-side randomize seed enabled, observed seed 1646387073, native 1024x1024, 2 inference steps, guidance 4.5, no prompt enhancement, no reference images, exact checkpoint Efficient-Large-Model/Sana_Sprint_0.6B_1024px_diffusers, Space commit b42328123ed688df4bee46e52c60cc1dc62c045a, generated Nov 1, 2026, 9:42 PM. Source

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

FLUX.2 Klein 9B Preview image SHA 256: 83bd206858a0d2bfab8a9d3bb7d90de6ff568017464a8168726175a6b324a90c

Sana-Sprint 0.6B 1024px image SHA 256: 17356f29ad7fa9644e9683ec624d0c01ad56ff0c14d078db5f78f3b6bcf6a45e

Infographic

FLUX.2 Klein 9B Preview: manual, BFL API /v1/flux-2-klein-9b-preview (distinct preview checkpoint); native 1024x1024, 1:1; one request, first output; seed=1679342581; output_format=png; no reference images or negative prompt, generated Nov 2, 2026, 7:06 PM. Source

Sana-Sprint 0.6B 1024px: manual, 1:1, one request, first output, one image, provider-side randomize seed enabled, observed seed 1798448399, native 1024x1024, 2 inference steps, guidance 4.5, no prompt enhancement, no reference images, exact checkpoint Efficient-Large-Model/Sana_Sprint_0.6B_1024px_diffusers, Space commit b42328123ed688df4bee46e52c60cc1dc62c045a, generated Nov 1, 2026, 9:42 PM. Source

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

FLUX.2 Klein 9B Preview image SHA 256: deb8da580546e3d22e20222c5c7e8c1a95197f27be4bff0b064eba603bda7b47

Sana-Sprint 0.6B 1024px image SHA 256: efbab43ef1980109bff4084afe6162c4915e4fb55185617adaac5713f20b5e24

Product photography

FLUX.2 Klein 9B Preview: manual, BFL API /v1/flux-2-klein-9b-preview (distinct preview checkpoint); native 1024x1024, 1:1; one request, first output; seed=132780547; output_format=png; no reference images or negative prompt; first provider output recovered by GET after local regional API validation stopped polling; no regeneration, generated Nov 2, 2026, 7:04 PM. Source

Sana-Sprint 0.6B 1024px: manual, 1:1, one request, first output, one image, provider-side randomize seed enabled, observed seed 520567323, native 1024x1024, 2 inference steps, guidance 4.5, no prompt enhancement, no reference images, exact checkpoint Efficient-Large-Model/Sana_Sprint_0.6B_1024px_diffusers, Space commit b42328123ed688df4bee46e52c60cc1dc62c045a, generated Nov 1, 2026, 9:42 PM. Source

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

FLUX.2 Klein 9B Preview image SHA 256: b1f17cd46fcd8f8b862da7c59900c1616ac3db8052d92a344720b7dc7fcb75ea

Sana-Sprint 0.6B 1024px image SHA 256: ac2d880a5b40924b518e25c61c5e077ffc9c5825f3eb896d733096ac6c631e46

Typography and layout

FLUX.2 Klein 9B Preview: manual, BFL API /v1/flux-2-klein-9b-preview (distinct preview checkpoint); native 1024x1024, 1:1; one request per attempt; two submissions; original signed output expired after local retrieval failure; first output of technical repeat with unchanged prompt and seed; seed=4230828387; output_format=png; no reference images or negative prompt, generated Nov 2, 2026, 7:06 PM. Source

Sana-Sprint 0.6B 1024px: manual, 1:1, one request, first output, one image, provider-side randomize seed enabled, observed seed 1229099615, native 1024x1024, 2 inference steps, guidance 4.5, no prompt enhancement, no reference images, exact checkpoint Efficient-Large-Model/Sana_Sprint_0.6B_1024px_diffusers, Space commit b42328123ed688df4bee46e52c60cc1dc62c045a, generated Nov 1, 2026, 9:42 PM. Source

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

FLUX.2 Klein 9B Preview image SHA 256: 6cc5a70118def87bf0ec737b20c9dd56c3a7dd3ec776e007b8a5fdadd4c27849

Sana-Sprint 0.6B 1024px image SHA 256: fd10095819c7746d6b52cc50e3d63f9d81eff271ad1edb4d3ba667a954098ac7

The numbers at a glance

Arena ratingfrom votes by users · higher is better

n/a

FLUX.2 Klein 9B Preview

not in the arena

n/a

Sana-Sprint 0.6B 1024px

not in the arena

GraduallyBenchour own rating, 0 to 100 · higher is better

FLUX.2 Klein 9B Preview

Rank 48 of 108

Sana-Sprint 0.6B 1024px

Rank 101 of 108

Price per imagedollars through the API · lower is better

n/a

FLUX.2 Klein 9B Preview

no API price

n/a

Sana-Sprint 0.6B 1024px

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 Preview

Subscription: n/a No plan in Germany names exactly this model.
Via API: No API price known. Access: API.
Weights: unknown.

Sana-Sprint 0.6B 1024px

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

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

GraduallyBench from Nov 3, 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 Preview	Sana-Sprint 0.6B 1024px
Ratings
Arena ratingfrom votes by users, higher is better	n/a	n/a
Arena rank	n/a	n/a
Arena votesmore votes, a safer rating	n/a	n/a
GraduallyBenchour own rating, 0 to 100	62	13
GraduallyBench by task
Typography and layoutLegible text, hierarchy, and composition	56	16
Product photographyMaterials, reflections, and fine details	73	19
Character and detailAnatomy, clothing, and spatial consistency	45	9
InfographicNumbers, labels, and visual organization	75	7
API price
Per imagelower is better	n/a	n/a
100 images	n/a	n/a
Profile
Released	n/a	Mar 22, 2025
Weightsopen means: runs locally	unknown	open
Lifecycle	Preview API route with newer quality/speed improvements; the stable 9B route remains separate	no notice
Access	API	local
Parameters	9 billion	0.6 billion
Largest output	not consistently published	not consistently published
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 Preview model source, status source (verified Nov 1, 2026) · Sana-Sprint 0.6B 1024px 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 Klein 9B Preview and Sana-Sprint 0.6B 1024px from the same arena and category. Older model versions are not used as substitutes.

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