Seedream 4.5vs.Nano Banana (Gemini 2.5 Flash Image)

Which one is better?

In our own test both are on par. 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.

Seedream 4.5: Character and detail, first image from the fixed test run — Seedream 4.537 out of 100

Nano Banana (Gemini 2.5 Flash Image): Character and detail, first image from the fixed test run — Nano Banana (Gemini 2.5 Flash Image)79 out of 100

Result for “Character and detail”:Nano Banana (Gemini 2.5 Flash Image) 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

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

Seedream 4.5: fal, requested native 2048x2048 square, n=1, seed=607017308, estimated cost $0.040000, source 2048x2048, stored 1024x1024 (Lanczos3 downscale), generated Nov 2, 2026, 2:50 PM. Source

Nano Banana (Gemini 2.5 Flash Image): fal, aspect ratio 1:1, n=1, seed=provider random, Fal schema does not expose an output-resolution parameter; require square output of at least 1024px, estimated cost $0.039800, generated Nov 1, 2026, 8:51 PM. Source

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

Seedream 4.5 image SHA 256: 614d5b810be9f7cc54c999fb930e5bb1a7a5b58f7211a3b71aa92e83a360cf78

Nano Banana (Gemini 2.5 Flash Image) image SHA 256: 69ecb842e42e25cf866919f9bfa573f08398a78d4fa46bca2f9c9c27996d80a7

Infographic

Seedream 4.5: fal, requested native 2048x2048 square, n=1, seed=467481828, estimated cost $0.040000, source 2048x2048, stored 1024x1024 (Lanczos3 downscale), generated Nov 2, 2026, 2:51 PM. Source

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

Seedream 4.5 image SHA 256: ec1e2be1080670edf050cff00a094ff471c1b480a11a3922cf8c25f0ef0f6a5e

Nano Banana (Gemini 2.5 Flash Image) image SHA 256: d12f93429b044d541a8ea71a1fd135f89343ff6efaefafe679e9e28699ee54cf

Product photography

Seedream 4.5: fal, requested native 2048x2048 square, n=1, seed=1880157282, estimated cost $0.040000, source 2048x2048, stored 1024x1024 (Lanczos3 downscale), generated Nov 2, 2026, 2:50 PM. Source

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

Seedream 4.5 image SHA 256: 48a36dede8c680fa8e2231ac33a95b1417dcded96ad753c98218cc78ed96a65b

Nano Banana (Gemini 2.5 Flash Image) image SHA 256: afdcf628727069979bcc9797a18b283079f9cafb136d8fcbc118ae1fc5523a15

Typography and layout

Seedream 4.5: fal, requested native 2048x2048 square, n=1, seed=775629027, estimated cost $0.040000, source 2048x2048, stored 1024x1024 (Lanczos3 downscale), generated Nov 2, 2026, 2:50 PM. Source

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

Seedream 4.5 image SHA 256: 62d4e5b0b3c9ca5a55952dc2c5aca878ed687c76f302ad632136bd3e6bee3872

Nano Banana (Gemini 2.5 Flash Image) image SHA 256: eeafdc566564b9398bc45b9e8cbaa7f4ca38a1b8795e198cd056c4bc47f72121

The numbers at a glance

Arena ratingfrom votes by users · higher is better

n/a

Seedream 4.5

not in the arena

n/a

Nano Banana (Gemini 2.5 Flash Image)

not in the arena

GraduallyBenchour own rating, 0 to 100 · higher is better

Seedream 4.5

Rank 64 of 108

Nano Banana (Gemini 2.5 Flash Image)

Rank 34 of 108

Price per imagedollars through the API · lower is better

n/a

Seedream 4.5

no API price

n/a

Nano Banana (Gemini 2.5 Flash Image)

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.

Seedream 4.5

Subscription: No ByteDance / Volcengine subscription includes this model. Through other providers from ≈ €6.36 a month (ElevenLabs Starter, with limited credits). 39 plans in Germany.
Via API: No API price known. Access: API, Web app.
Weights: unknown.

Nano Banana (Gemini 2.5 Flash Image)

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

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	Seedream 4.5	Nano Banana (Gemini 2.5 Flash Image)
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	48	66
GraduallyBench by task
Typography and layoutLegible text, hierarchy, and composition	84	68
Product photographyMaterials, reflections, and fine details	44	81
Character and detailAnatomy, clothing, and spatial consistency	37	79
InfographicNumbers, labels, and visual organization	27	36
API price
Per imagelower is better	n/a	n/a
100 images	n/a	n/a
Profile
Released	n/a	Oct 2, 2025
Weightsopen means: runs locally	unknown	unknown
Lifecycle	Still-listed T2I/I2I model ID; Ark marks it as pending shutdown without giving a date in the reviewed source	Active stable API ID; earliest announced shutdown date is March 15, 2027
Access	API, Web app	API
Parameters	not published	not published
Largest output	not consistently published	not consistently published
Plans in Germanynaming exactly this model	39	n/a

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

Sources: Seedream 4.5 model source, status source (verified Nov 1, 2026) · Nano Banana (Gemini 2.5 Flash Image) model source, status 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 Seedream 4.5 and Nano Banana (Gemini 2.5 Flash Image) from the same arena and category. Older model versions are not used as substitutes.

More comparisons

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