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Image model comparison · 2 models · Updated Nov 2, 2026

FLUX.2 [flex] vs Seedream 4.5

Preferred for text to image: FLUX.2 [flex] · Preferred for image editing: Seedream 4.5 · Newest: Seedream 4.5. Quality scores are blind human-preference votes; specs and prices come from each lab’s listings.

  1. Black Forest Labs

    FLUX.2 [flex]

    Released Nov 25, 2025

    • Text to image
    • Image editing
    • Arena1,224
    • From$0.05/image
    • Max size—
    Full specs Remove FLUX.2 [flex]

  2. ByteDance Seed

    Seedream 4.5

    Released Dec 3, 2025

    • Text to image
    • Image editing
    • Arena1,303
    • From—
    • Max size—
    Full specs Remove Seedream 4.5

  3. Add a model

    Make it a three-way comparison.

01 — At a glance

Where they differ

Quality is the arena score from blind, side-by-side human votes. Price, length and resolution come from each lab’s own listings.

  • Preferred for text to imageFLUX.2 [flex]FLUX.2 [flex] 1,156 (#30) · Seedream 4.5 1,149 (#35) — blind human votes
  • Preferred for image editingSeedream 4.5FLUX.2 [flex] 1,224 (#43) · Seedream 4.5 1,303 (#27) — blind human votes
  • NewestSeedream 4.5FLUX.2 [flex] Nov 25, 2025 · Seedream 4.5 Dec 3, 2025
  • Widest inputsSame inputsFLUX.2 [flex]: Text prompts, Reference images · Seedream 4.5: Text prompts, Reference images
  • Image editingBoth edit imagesTakes a reference image as input: FLUX.2 [flex] yes · Seedream 4.5 yes
  • Self-hostingNo open weightsBoth are available only through APIs and apps
  • Most API hostsSame reachFLUX.2 [flex]: 1 · Seedream 4.5: 1
02 — Side by side

Every spec in one table

Dashes mean the data is not published.

FLUX.2 [flex] vs Seedream 4.5 specifications side by side
SpecificationFLUX.2 [flex]Black Forest LabsSeedream 4.5ByteDance Seed
Quality (blind human votes)
Text to image arenaElo-style score · higher is better1,156 ±3#30 of 82 · 156,876 votes (best)1,149 ±3#35 of 82 · 318,120 votes
Image editing arenaElo-style score · higher is better1,224 ±3#43 of 61 · 443,912 votes1,303 ±2#27 of 61 · 1,361,328 votes (best)
Price
Starting price$0.05/image 1 MP—
How it is billedBilled per megapixel.—
Output
ProducesImagesImages
Images per requestUp to 1—
Inputs
Text promptsYesYes
Reference images (editing)YesYes
Max reference images8—
Access
WeightsProprietaryProprietary
API hosts11
ReleasedNov 25, 2025Dec 3, 2025
03 — Questions

Which should you choose?

Which is better, FLUX.2 [flex] or Seedream 4.5?

For text to image, voters prefer FLUX.2 [flex] (FLUX.2 [flex] 1,156 (#30) · Seedream 4.5 1,149 (#35)). For image editing, voters prefer Seedream 4.5 (FLUX.2 [flex] 1,224 (#43) · Seedream 4.5 1,303 (#27)). Arena scores come from blind, side-by-side human votes on the same prompts; when the gap is inside both models’ error margins we call it a tie. Test your own prompts before you commit.

Which is cheaper?

FLUX.2 [flex] costs from $0.05/image (1 MP). Seedream 4.5 has no published per-image price. Prices are list rates and change often; check the lab before budgeting.

What is the difference between FLUX.2 [flex] and Seedream 4.5?

FLUX.2 [flex] is an image model from Black Forest Labs (Nov 25, 2025), taking text prompts and reference images and producing images. Seedream 4.5 is an image model from ByteDance Seed (Dec 3, 2025), taking text prompts and reference images and producing images.

Which is newer?

FLUX.2 [flex] Nov 25, 2025; Seedream 4.5 Dec 3, 2025.

Which can edit an existing image?

Takes a reference image as input: FLUX.2 [flex] yes; Seedream 4.5 yes.

Can I run any of these on my own hardware?

No open weights. Both are available only through APIs and apps.

04 — Keep comparing

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