# Seedream on BytePlus ModelArk (slim)

> BytePlus ModelArk's hosted API for ByteDance's Seedream image models. One endpoint handles text-to-image, reference-image editing, batches of related images and layer decomposition, billed per generated image.

- Full: https://www.anchorterminal.com/tools/seedream-on-byteplus-modelark.md (~7,600 tokens) · this version ~1,730 tokens · JSON https://www.anchorterminal.com/tools/seedream-on-byteplus-modelark.json · canonical https://www.anchorterminal.com/tools/seedream-on-byteplus-modelark
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · Updated: 2026-10-10

**D · 53.8/100 · rank #700 of 950 · #5 in Image generation · not agent-ready · confidence medium**


Assessment: Per-image prices from $0.018 are public, and API keys can be limited to named models and an IP allowlist. No status page, SLA or OpenAPI file was found, onboarding needs a browser sign-up, and BytePlus says its model services are not available in the United States.

## Facts

- Kind: Model API · vendor: BytePlus Pte. Ltd. (ByteDance) · category: Image generation · legal entity: BytePlus Pte. Ltd. · provenance 59/100
- Endpoint: `https://ark.ap-southeast.bytepluses.com/api/v3` (HTTP)
- Auth: API key · pricing: Pay per use · x402: no · licence: Proprietary service under the BytePlus Customer Agreement and Service Specific Terms. The Go and Python SDK repositories are Apache-2.0
- Probe metrics: not measured yet (probes haven't run)
- Models: `dola-seedream-5-0-pro-260628`, `dola-seedream-5-0-flash-260915`, `seedream-5-0-260128` (also `seedream-5-0-lite-260128`), `seedream-4-5-251128`, `seedream-4-0-250828`
- Max resolution: 4K (4096x4096, 16.8 million pixels) on Seedream 5.0 lite, 4.5 and 4.0. 2K (up to 4.62 million pixels) on 5.0 pro and flash
- Edit support: Yes. Prompt edits with up to 10 reference images on 5.0 pro and flash, up to 14 on the others. Interactive editing by coordinates, boxes and arrows and layer decomposition on 5.0 pro and flash only
- Batch output: `sequential_image_generation` on 5.0 lite, 4.5 and 4.0. Input plus output images at most 15. Streaming on the same three models
- Output: URL valid for 24 hours or `b64_json`. JPEG by default, PNG on the 5.0 models. Transparent background on 5.0 pro and flash
- Watermark: An AI-generated mark in the lower right corner by default. `watermark: false` removes it
- Rate limits: 500 images a minute per model per account, stated as a theoretical maximum. Higher limits by ticket
- Regions: ap-southeast-1 (Johor) at ark.ap-southeast.bytepluses.com and eu-west-1 (Dublin) at ark.eu-west.bytepluses.com. The region page lists only `seed-2-0-lite` as an EU model
- Availability: A published list of countries and regions, last updated 21 April 2026. The terms say the model services are not available in the United States
- SDKs: Python (`arkruntime`, legacy `byteplus-python-sdk-v2` v3.0.61 of 17 September 2026), Go (`ark-runtime-go` v0.9.0 of 17 September 2026), Java (`com.volcengine:ark-runtime`). The OpenAI SDK works with the base URL changed
- Data handling: No training on customer data unless the customer opts in. Filter-triggered input and output kept 180 days in Malaysia. Processing in Malaysia, Indonesia and the EU or EEA
- Certifications: The trust centre lists ISO 27001, 27017, 27018 and 27701, SOC 1, 2 and 3, PCI DSS, CSA STAR and MTCS Level 3 for BytePlus as a whole
- Free tier: None listed for Seedream. The free trial page covers models billed by token
- Prices: Seedream 5.0 flash $0.018 per image; Seedream 4.0 $0.03 per image; Seedream 5.0 lite $0.035 per image; Seedream 4.5 $0.04 per image; Seedream 5.0 pro $0.045 per image; Seedream 5.0 pro above 1.5K $0.09 per image

- Scores: Reliability 43, Performance pending, Schema & documentation 62, Agent ergonomics 72, Security & auth 70, Payments & pricing 20, Task success pending, Maintenance & community 73, Transparency & trust 60 · negative events -3 · total over the 7 assessed categories
- Why: Reliability, Graded as a hosted service. · Schema & documentation, No OpenAPI file for the data plane was found. · Agent ergonomics, Graded on the model lines. · Security & auth, API keys are scoped to a resource project and region, can be limited to named model IDs or endpoints and to an IP allowlist, and can be disa… · Payments & pricing, No x402, MPP or L402 (0). · Maintenance & community, Graded on the model lines. · Transparency & trust, Closed service under a public Customer Agreement and Service Specific Terms.
- Sources: 27, open questions: 10, both in the full twin
- Capabilities: image.generate, image.edit, image.reference
- JSON: https://www.anchorterminal.com/api/v1/tools/seedream-on-byteplus-modelark.json
- Verify (for the vendor): the badge `https://www.anchorterminal.com/badges/seedream-on-byteplus-modelark.svg` or a link to https://www.anchorterminal.com/tools/seedream-on-byteplus-modelark from a page on byteplus.com or one of its subdomains, or the README of github.com/volcengine/ark-runtime-go, then `POST https://www.anchorterminal.com/api/v1/verify` `{"slug", "url"}` or `verify_listing` at /mcp; re-checked weekly, no effect on the grade. Snippets in the full twin.

## Before you call it

1. POST to `https://ark.ap-southeast.bytepluses.com/api/v3/images/generations` with `Authorization: Bearer $ARK_API_KEY`. Keys and model activation are per region
2. Set `watermark` to false if the image must not carry the AI-generated mark. The default is true
3. Download `data[].url` within 24 hours, or ask for `response_format` `b64_json`
4. Check each `data[].error` in a sequential batch. One moderated image does not fail the others, and only `usage.generated_images` is billed
5. Stay under 500 images a minute per model and back off with jitter on 429. Layer decomposition reserves 17 against that limit per request

## Connect

```bash
python -m pip install --upgrade arkruntime
```

```bash
curl https://ark.ap-southeast.bytepluses.com/api/v3/images/generations \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $ARK_API_KEY" \
  -d '{"model":"seedream-5-0-lite-260128","prompt":"A lighthouse at dusk","size":"2K","output_format":"png","watermark":false}'
```

## Similar tools

| Tool | Grade | Score | Shared capabilities | Slim |
| --- | --- | --- | --- | --- |
| OpenAI Image API | BB | 72.4 | image.generate, image.edit, image.reference | https://www.anchorterminal.com/tools/openai-image-api.min.md |
| fal image models | B | 65.2 | image.generate, image.edit, image.reference | https://www.anchorterminal.com/tools/fal-image.min.md |
| Black Forest Labs FLUX API | B | 63.9 | image.generate, image.edit, image.reference | https://www.anchorterminal.com/tools/black-forest-labs.min.md |
| Bria API | B | 63.7 | image.generate, image.edit, image.reference | https://www.anchorterminal.com/tools/bria.min.md |
| Recraft API | D | 52.8 | image.generate, image.edit, image.reference | https://www.anchorterminal.com/tools/recraft.min.md |


## Panel reviews (0, desk reviews from public material, no calls made)