GPT Image 2.5 Sunburstvs.HiDream-O1-Image-1.5

Which one is better?

In our own test both are on par. HiDream-O1-Image-1.5 has no arena rating yet. GPT Image 2.5 Sunburst costs 2.6 times as much per image.

Test images

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

GPT Image 2.5 Sunburst: Product photography, first image from the fixed test run — GPT Image 2.5 Sunburst87 out of 100

HiDream-O1-Image-1.5: Product photography, first image from the fixed test run — HiDream-O1-Image-1.551 out of 100

Result for “Product photography”:GPT Image 2.5 Sunburst 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

GPT Image 2.5 Sunburst: openai, 1024x1024, quality high, n=1, generated Sep 28, 2026, 8:51 PM. Source

HiDream-O1-Image-1.5: manual, one request, first output, HiDream O1 Image 1.5, 1:1, 2K, n=1, no reference image, no negative prompt, Vivago web, 2 free credits, source 2048x2048, stored 1024x1024 (Lanczos3 downscale), generated Aug 16, 2026, 1:07 PM. Source

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

GPT Image 2.5 Sunburst image SHA 256: 2bcd5e2358dbf9e2f11336ebf6c4a4a15e0a9a10261dd74378d40985ac68ec6d

HiDream-O1-Image-1.5 image SHA 256: 99db95d2f6f00dc7f8872b5562b7577a49065a120d15fc54f687ba624fe4cf6e

Infographic

GPT Image 2.5 Sunburst: openai, 1024x1024, quality high, n=1, generated Sep 28, 2026, 8:52 PM. Source

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

GPT Image 2.5 Sunburst image SHA 256: 7dab94e5588be73aefe08f23f9d56ced4e2ddb2b29f754db41b057025cf34847

HiDream-O1-Image-1.5 image SHA 256: 073d00d82d82a05c20f9117a18e71e21fe0300fd9f4985608be09726b1ee70a8

Product photography

GPT Image 2.5 Sunburst: openai, 1024x1024, quality high, n=1, generated Sep 28, 2026, 8:51 PM. Source

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

GPT Image 2.5 Sunburst image SHA 256: c648276704e06f7925f2325e8ffff0d9d0a9bd6c5bb4866785abac92ce97ff9a

HiDream-O1-Image-1.5 image SHA 256: 98de28b81a3551441936ce2ebcc0b418e69e9d5cf6ce8b1dc281bc90b05731dc

Typography and layout

GPT Image 2.5 Sunburst: openai, 1024x1024, quality high, n=1, generated Sep 28, 2026, 8:50 PM. Source

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

GPT Image 2.5 Sunburst image SHA 256: fd6a3767ba8253869cb94d5346f025541dac924c2190df2c37b366b182986cf8

HiDream-O1-Image-1.5 image SHA 256: db5acbc9b443ea381bf6294997720fa246cf8a199f91d451aa1d7242fc4a348a

The numbers at a glance

Arena ratingfrom votes by users · higher is better

1,427

GPT Image 2.5 Sunburst

Rank 1 of 21

n/a

HiDream-O1-Image-1.5

not in the arena

GraduallyBenchour own rating, 0 to 100 · higher is better

GPT Image 2.5 Sunburst

Rank 8 of 108

HiDream-O1-Image-1.5

Rank 38 of 108

Price per imagedollars through the API · lower is better

$0.21

GPT Image 2.5 Sunburst

expensive

$0.08

HiDream-O1-Image-1.5

fairly expensive

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.

GPT Image 2.5 Sunburst

Subscription: No OpenAI subscription includes this model. Through other providers from ≈ €6.39 a month (ElevenLabs Starter, with limited credits). 62 plans in Germany.
Via API: $0.21 per image, 100 images $21.07.

HiDream-O1-Image-1.5

Subscription: n/a No plan in Germany names exactly this model.
Via API: $0.08 per image, 100 images $8.

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 3, 2026 · API prices from Nov 3, 2026 · Subscription database from Sep 29, 2026 (35 days old)

All data side by side

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

Kennzahl	GPT Image 2.5 Sunburst	HiDream-O1-Image-1.5
Ratings
Arena ratingfrom votes by users, higher is better	1,427	n/a
Arena rank	Rank 1 of 21	n/a
Arena votesmore votes, a safer rating	40,323	n/a
GraduallyBenchour own rating, 0 to 100	75	65
GraduallyBench by task
Typography and layoutLegible text, hierarchy, and composition	54	76
Product photographyMaterials, reflections, and fine details	87	51
Character and detailAnatomy, clothing, and spatial consistency	64	58
InfographicNumbers, labels, and visual organization	97	76
API price
Per imagelower is better	$0.21	$0.08
100 images	$21.07	$8
Profile
Released	Sep 8, 2026	June 2026
Weightsopen means: runs locally	proprietary	proprietary
Access	API	API, Web app
Parameters	not published	not published
Largest output	3,840 × 2,160 pixels	2,048 × 2,048 pixels
Plans in Germanynaming exactly this model	62	n/a

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

Sources: GPT Image 2.5 Sunburst model source (verified Sep 24, 2026) · HiDream-O1-Image-1.5 model source (verified Sep 22, 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 betterGPT Image 2.5 SunburstHiDream-O1-Image-1.5

Text to Image Arena1,2231,017ahead

Artificial Analysis from Nov 3, 2026

All individual values with sources

Rating	GPT Image 2.5 Sunburst	HiDream-O1-Image-1.5	Source
Text to Image Arena	1,223	1,017	Artificial AnalysisRetrieved Nov 3, 2026

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Predecessor and successor

PredecessorGPT Image 2.5 Sunburst vs. GPT Image 2Predecessor of GPT Image 2.5 Sunburst
GPT Image 2.5 Sunburst has no successor yet
No predecessor recorded for HiDream-O1-Image-1.5
HiDream-O1-Image-1.5 has no successor yet

Test images

The numbers at a glance

GPT Image 2.5 Sunburst

HiDream-O1-Image-1.5

All data side by side

Arena ratings by category

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Predecessor and successor

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