Model comparisons
Seedream 5.5 or Z-Image Spicy, tier by tier: matched prices, request fields, limits and the content policy measured on each.
Seedream 5.5 is ByteDance's newest image model, the successor to Seedream 5.0 Pro. It adds 4k output and transparent PNGs straight from a prompt, two things 5.0 Pro text to image lacks, keeps small multilingual text readable, and costs less at every size the two share.
View model details →View sample outputs →Z-Image Spicy is an uncensored text-to-image endpoint with exact width and height set independently from 256 to 1536 pixels. The prompt has no character cap, and the prompt expander is off unless you switch it on.
View model details →View sample outputs →Compare
Start with the input you have, the result you want and your budget. These are the differences that affect that choice.
Compare the published examples, then try the same input on both models with matching settings.
The Spicy Index and Freedom Score for both models, from the same daily calculation as the leaderboards.
| Measure | Seedream 5.5 | Z-Image Spicy |
|---|---|---|
| Spicy Index | 84.5 | 73.7 |
| Freedom Score | 97.8 | 98.8 |
| Evidence | Tested 6 of 6 probe types · 54 runs | Tested 6 of 6 probe types · 19 runs |
| Range if the rest pass | 97.8–97.8 | 98.8–98.8 |
| Price | $0.0195 per image | $0.0124 per image |
| Reviews | Read the Seedream 5.5 review | Read the Z-Image Spicy review |
Current price
A start price answers a different question than the one you have. These are the tiers both models publish, matched setting for setting, in US dollars per billed unit with no conversion step in between.
These two bill on different tiers, so there is no row to line up. Each one's own published tiers are listed here instead.
Seedream 5.5: 1.5k $0.019 / output images · 1K $0.019 / output images · 2K $0.027 / output images · 4K $0.052 / output images
Z-Image Spicy: Prompt expansion: No $0.012 / output images · Prompt expansion: Yes $0.013 / output images
Arithmetic on the published rates at each model's own default setting, not a quote. The console prices your actual settings before a request is accepted.
About this comparison
Every row here is read from the JSON Schema the endpoint validates against, so it matches what the API will really accept rather than a feature list written by hand.
Swipe horizontally to compare all fields.
| Controls and limits | Seedream 5.5 | Z-Image Spicy |
|---|---|---|
| Supported tasks | text-to-image | text-to-image |
| Resolution tiers | 1K · 1.5k · 2K · 4K | Not offered |
| Aspect ratios | 1:1 · 4:3 · 3:4 · 16:9 · 9:16 · 3:2 · 2:3 · 21:9 | Not offered |
| High-resolution tier | Yes | No |
| Seed | No | Yes |
| Execution | Submit, then poll or take the callback | Submit, then poll or take the callback |
| Request timeout | 30 minutes | 180 minutes |
| Availability | Live | Live |
Do low-filter models allow every request?
Two separate facts sit behind these labels. The first is what we do, which is nothing: no platform content filter, and no maturity flag to set on a request. The second is what each model does on its own, and that is the only part that varies between these two.
Seedream 5.5
This model declares no content filter. SpicyAPI forwards the request without adding a platform content scan; legal and consent duties remain with the customer.
Usage note Seedream 5.5 generates images from text without content filtering. Any people you depict must be consenting adults, and you are responsible for the images you generate.
Z-Image Spicy
This model declares no content filter. SpicyAPI forwards the request without adding a platform content scan; legal and consent duties remain with the customer.
Use these content labels to shortlist models, then open each model page for available examples and content-test details.
The label never changes your obligations. Age, consent, real-person likeness and the law where you operate stay with you, and SpicyAPI does not inspect each request.
Can I swap the model ID without changing the request body?
The task lifecycle is shared; the body is not. Each endpoint publishes its own JSON Schema and the API validates against that, so this is the list to reconcile before a switch.
How to choose
Seedream 5.5 supports a high-resolution option.
Compare
The model identifiers are bytedance/seedream-5.5/text-to-image and alibaba/z-image-spicy/text-to-image, and both go in the same field of the same request.
Both run the same way: submit the task, then poll it or take the callback. Queueing and retry logic carry over unchanged.
Both use the same submit-and-track flow, but their required inputs may differ. Check each model page before switching.
One key, one balance, one set of spend caps. Both bill to the same account in US dollars, and the per-key daily, monthly and lifetime limits apply to whichever one you call.
Questions developers ask
The two bill on different tiers, so there is no like-for-like row: Seedream 5.5 starts at $0.019 / output images and Z-Image Spicy at $0.012 / output images. Prices may change; check the estimate shown for your actual settings before submitting.
Seedream 5.5 allows 30 minutes per task and Z-Image Spicy allows 180. Those are ceilings rather than typical times — most requests finish far sooner — but they are what your own client timeout has to survive.
Prices and capabilities shown here come from the current public model catalogue. Check each model page for its latest inputs and examples.