Comparison · Image models
Seedream 5.0 Pro vs GPT Image 2.5
Seedream 5.0 Pro or GPT Image 2.5? Near-equal scores in my test, but GPT costs about 1.8x less and handles Polish text better. Seedream has 2K and 16:9.
Specs side by side
| Seedream 5.0 Pro | GPT Image 2.5 | |
|---|---|---|
| Vendor | ByteDance | OpenAI |
| Type | Image | Image |
| Modes | text-to-image image-to-image | text-to-image image-to-image |
| Released | 2026-07 | 2026-09 |
| Resolutions | 1K, 1.5K, 2K | - |
| Aspect ratios | 1:1, 4:3, 3:4, 16:9, 9:16, 2:3, 3:2, 21:9 | auto, 1024x1024, 1536x1024, 1024x1536 |
| Reference images | up to 10 | up to 16 |
| Prompt length | up to 32,000 chars | up to 32,000 chars |
| Quality | - | auto, low, medium, high, xhigh, max |
Price per unit and per clip
| Model | Variant | Rate |
|---|---|---|
| Seedream 5.0 Pro | 1K | $0.0783 / image |
| 2K | $0.157 / image | |
| GPT Image 2.5 | - | $0.0432 / image |
Prices exclude taxes and are charged from your prepaid USD balance. Failed generations cost nothing.
On the same five prompts Seedream 5.0 Pro and GPT Image 2.5 got almost identical scores from me. GPT Image 2.5, however, costs about 1.8 times less, charges the same at every quality level (including max), was faster and wrote Polish text without errors. Pick Seedream 5.0 Pro when you need a 2K image or formats such as 16:9, 9:16, 4:3 or 21:9, which GPT Image 2.5 does not offer on Jantaris.
Key differences
- Formats. GPT Image 2.5 has three: 1024x1024, 1536x1024 (3:2) and 1024x1536 (2:3), plus
auto. Seedream 5.0 Pro has 8 ratios (1:1, 4:3, 3:4, 16:9, 9:16, 2:3, 3:2, 21:9) at 1K, 1.5K and 2K. - Quality. In GPT Image 2.5 you choose
low,medium,high,xhighormax, and the price does not change. Seedream has no such switch; you pay by resolution tier. - References. GPT Image 2.5 up to 16 images (the request then works as an edit), Seedream up to 10.
- Text. Both are meant for graphics with lettering, but in my tests only GPT Image 2.5 wrote Polish without errors.
- Shared. One image per request, prompts up to 32,000 characters.
When to pick Seedream 5.0 Pro
- A 2K image for print or a large screen.
- 16:9 or 9:16 straight from the model, no cropping.
- 21:9 or 4:3 framing.
- A portrait or reportage shot with natural side light.
When to pick GPT Image 2.5
- Graphics with text in a language that uses diacritics.
- A batch where the cost of each image counts.
- Photo edits with up to 16 references.
- Top quality (
max) at no extra cost.
Cost in practice
Seedream 5.0 Pro at 1K costs about 1.8 times as much as GPT Image 2.5, and at 2K about 3.6 times as much. GPT Image 2.5 has a flat price regardless of quality, format and number of references, so on Jantaris there is no reason to save on quality. In Seedream the 1.5K tier costs the same as 1K for some ratios, and every reference image after the first adds a small amount. Rates: from $0.0783 per image (1K) and $0.0432 per image; everything on /pricing.
Both models got the same five prompts from me for promptowy.com (Polish blog, on another provider, 16:9). Seedream 5.0 Pro: 8.5/10 in my image generator ranking, 45.6 s per image on average, the best light in the portrait. GPT Image 2.5: 8.5/10 at high and 8.6 at max (my GPT Image 2.5 test), about 18 s at high and about 38 s at max. GPT Image 2.5 wrote a Polish shop sign correctly at every quality level. Seedream got it right in the ranking but added stray diacritics in my typography test. Wider comparison: GPT Image 2.5 vs Nano Banana Pro vs FLUX.2.
FAQ
Seedream 5.0 Pro or GPT Image 2.5: which is better?
On image quality my test was a tie (8.5 vs 8.5-8.6). GPT Image 2.5 wins on price, speed and Polish text; Seedream wins on 2K resolution and formats.
Does GPT Image 2.5 do 16:9?
Not on Jantaris. You get square, 3:2 landscape, 2:3 portrait or auto. For native 16:9 use Seedream 5.0 Pro.
Does higher quality cost more in GPT Image 2.5?
No. On Jantaris every GPT Image 2.5 image costs the same, from low to max.
Which handles text better?
For Polish, GPT Image 2.5, with no errors at any quality in my test. In Seedream 5.0 Pro I check every accented letter by hand.
Vendor examples
Seedream 5.0 Pro


GPT Image 2.5


Official examples from the model vendors, not our generations.








