Seedream 4.5 API

About Seedream 4.5

Exact text in 2K and 4K images, with edits from up to 14 references.

Call it with the model name bytedance/seedream-4.5/text-to-image on POST /jobs/createTask, from $0.04.

Introduction

Seedream 4.5 Text to image draws one image from a written prompt on Seedream 4.5, ByteDance's image model, at 2K or 4K in eight aspect ratios. For changing or combining pictures, use Seedream 4.5 Image Editing.

Choose a model by what you need

Key features

Text that comes out as quoted

A film poster with its title and bottom line and a perfume bottle with its engraved name were spelled correctly in our tests. ByteDance says text rendering is better in 4.5. We only tried English.

Eight ratios

From 21:9 to 9:16. At 2k, 16:9 is 2848 x 1600, 3:2 is 2496 x 1664 and 1:1 is 2048 x 2048.

Request parameters

Pricing

Prices are in USD. The API uses a separate USD balance. Website credits cannot be used or transferred to it, and API funds cannot be transferred to website credits. When a task is accepted, we reserve the maximum quoted amount from your API balance. On completion, we charge for actual usage, never more than the hold, and release the remainder. If the task fails, the hold is released.

Send the same request body to POST /jobs/quote to see the estimated and maximum USD charge before running. A quote does not run the task or charge your balance.

Use cases

Posters and ads

A title, a tagline and a product name in one picture. Quote each string and place it.

Cinematic frames

Wide 21:9 and 16:9 stills with a lens, a palette and a light source named.

Group scenes and portraits

Four friends at a pool, a couple dancing close, a boxer in an old gym: several people with their own outfits in one frame.

Prompt guide & pro tips

Quote the text, then place it

Write "NOIR VELOURS" in quotes, then say where it goes and how it looks: engraved in gold on the bottle. Keep the strings short enough to read at the size you choose.

Name the light and the lens

A single beam of warm gold light from the left, 50mm, shallow depth of field, film grain. These details shape the result more than adjectives do.

Give each person their own sentence

For group scenes, describe each person by outfit and action in turn, as in the four-friends pool prompt.

Plan for different results

There is no seed, so the same prompt returns a different image each time. Save the ones you like and keep the prompt with them.

Describe what you want

There is no negative prompt. Say what is in the frame, not what to leave out.

API quick start

Call the Seedream 4.5 API in three steps

1. Create an API key. Sign in to PopNow and create a key in the API console. Keys start with sk-popnow-. API calls use your separate USD balance.
2. Send the request. POST /jobs/createTask with model bytedance/seedream-4.5/text-to-image and an input object that follows the parameter table. The response returns a task ID straight away.
3. Get the result. Poll GET /jobs/recordInfo with the task ID, or pass a callBackUrl and we post the result to it. Download the output links when the task succeeds.

# 1. Create the task. Keep the Idempotency-Key if you retry after a network error.
export IDEMPOTENCY_KEY="$(uuidgen)"
curl -X POST https://api.popnow.ai/api/v1/jobs/createTask \
  -H "Authorization: Bearer $POPNOW_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: $IDEMPOTENCY_KEY" \
  -d '{
  "model": "bytedance/seedream-4.5/text-to-image",
  "input": {
    "prompt": "A ceramic teapot on a linen cloth, soft window light, muted palette",
    "aspect_ratio": "1:1",
    "resolution": "2k"
  }
}'

# 2. Copy data.taskId from the response, then poll until state is succeeded, failed, canceled or expired.
TASK_ID="TASK_ID_FROM_RESPONSE"
curl "https://api.popnow.ai/api/v1/jobs/recordInfo?taskId=$TASK_ID" \
  -H "Authorization: Bearer $POPNOW_API_KEY"

Replace the prompt and any links with your own. The API tab has the response, polling and callback reference.

Seedream 4.5 API questions

All Seedream models

• Seedream 5.0 Pro APIHigh-detail images and edits from up to ten referencesFrom $0.036 per image
• Seedream 5.0 Flash APIQuick Seedream images, edits and layer splits up to 2KFrom $0.026 per image
• Seedream 5.0 Lite APIFixed-size 2K frames that keep a series consistentFrom $0.0345 per image
• Seedream 4.5 APIExact text in 2K and 4K images, with edits from up to 14 referencesFrom $0.04 per image
• Seedream 4.0 APIExact sizes up to 4096×2304 and ten-reference editsFrom $0.03 per image

Other image APIs

• Nano Banana Pro APIPlans the layout first: dense text, diagrams and 4K editsFrom $0.1072 per image
• GPT Image 2.5 Sunburst APIOpenAI's quality-first model, up to 4K with clean textFrom $0.00182 per image
• FLUX.2 Max APITop-tier FLUX: photoreal light and exact brand colorsFrom $0.07 per image
• Qwen Image 2.1 Pro APIUp to six detailed 2K images from one promptFrom $0.036 per image

More about Seedream 4.5

Try it

Seedream 4.5 AI Image Generator onlineCreate images with Seedream 4.5 in PopNow

Endpoints

Seedream 4.5 · Edit Image

Docs

Seedream 4.5 model ID and input schema in the API docsPopNow API quickstart: your first request in five minutesImage generation guide for the PopNow APIWebhooks: get Seedream 4.5 results without polling