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Seedance 2 Mini

Generate 4–15 second videos at 480p or 720p at the lowest list price in the Seedance family (see Billing), from text, a first and last frame, or up to 9 images, 3 videos and 3 audio clips as references.

  • Asynchronous: the create call returns a task ID; the video arrives when the task succeeds (usually a few minutes).
  • Four ways in: text only, a first frame, a first and last frame, or reference images, videos and audio in any mix (audio needs at least one image or video beside it).
  • 480p and 720p only, at the lowest list price in the Seedance family (see Billing).
  • There is no generate_audio field on this model: sending it is refused. Use Seedance 2.0 or 2.0 Fast to control sound.
  • Billed by the size and length of the video, plus the length of any reference videos. A failed task costs nothing.
POST/v1/videos/tasksTry it

Opens this model in the API Explorer. Enter your BeatAPI API key to create a task: the call is real and is billed to your own balance.

Model IDs

Four Seedance models share this endpoint. The values below come straight from the gateway contract; only Seedance 2.5 accepts task_type, output_format and seed.

Model IDduration (s)resolutionMax reference imagesMax reference videosMax reference audioChoose it when
seedance-2.54–30480p, 720p, 1080p301010You need clips up to 30 seconds, large reference sets, editing or extending a video, or MOV output.
seedance-24–15480p, 720p, 1080p, 4k933You need 4K output, or 1080p at a lower price than 2.5.
seedance-2-fast4–15480p, 720p933You want a lower price at 480p or 720p and keep generate_audio.
seedance-2-mini4–15480p, 720p933Price matters most; 480p or 720p, no generate_audio field.

Endpoint and authentication

POST https://api.beatapi.io/v1/videos/tasks

Authorization string Required

Your BeatAPI API key, sent as Bearer <BEATAPI_API_KEY>. Create keys in the Dashboard. Keep keys on your server; never ship them in a browser or mobile app.

Send the body as JSON with Content-Type: application/json. Idempotency-Key is optional: send a unique value (at most 255 characters) per logical request and reuse it only to retry that exact body. Within 24 hours a retry with the same key and body returns the first response again with Idempotent-Replayed: true; the same key with a different body returns 409 idempotency_conflict. Responses other than 2xx are not stored, so a retry after a 400 or 402 runs again.

How a request works

1

Create the task

POST the parameters below to the endpoint. A 201 means the task was accepted and its price reserved from your balance; the work runs in the background. Save data.id.

2

Wait for it to finish

Call GET /v1/tasks/{task_id} and wait data.poll_after_seconds between calls (5 s for images, 8 s for videos) until status is succeeded or failed. Or register a webhook for task.succeeded and task.failed; keep polling as the fallback, because a task stopped by the processing timeout sends no event.

3

Save the result

On succeeded, download every data.output.media[].url and store the files you need; BeatAPI does not promise how long result URLs stay available. On failed, read data.error_code and data.error_message: the reserved amount was returned to your balance, and data.retryable says whether sending the same request again can succeed.

Input modes

ModeRequired inputsNotes
Text to videomodel, promptSend no media arrays.
First framemodel, prompt, images (1 link)The video starts from the image.
First and last framemodel, prompt, images (2 links)images[0] is the first frame, images[1] the last.
Referencesmodel, prompt, at least one of reference_images, reference_videos, reference_audiosAny mix, but audio needs at least one reference image or video beside it. Cannot be combined with images.

Request parameters

model string Required

The model to run.

Value: seedance-2-mini

If the value is wrong

  • Missing: "model" is required
  • An image model sent to this endpoint: "model" nano-banana-2 is served by POST /v1/images/tasks, not this endpoint

prompt string Required

What happens in the video: subject, action, camera movement, style and sound. With references, say what each input is for.

Length: 1–5000 characters

  • Length is counted in characters (a CJK character counts as one).
  • Refer to inputs by their position, for example “the first reference image” or “the second reference video”.

If the value is wrong

  • Missing: "prompt" is required
  • Empty or longer than the limit: "prompt" has an unsupported length

images string[] Optional

A first frame, or a first and a last frame.

Items: 1–2
Each item is a public https:// URL. For a local file, upload it first with POST /v1/files and pass the returned data.url.

  • One link: the video starts from this image. Two links: images[0] is the first frame and images[1] the last.
  • For more pictures, or pictures that guide the video without being frames, use reference_images instead.

If the value is wrong

  • More than two links: "images" accepts at most 2 items
  • Combined with any reference_* field: Cannot combine "images" with reference inputs in one task
  • Not an https:// link: "images[0]" must be a public HTTPS URL

reference_images string[] Optional

Pictures that guide the content, characters, products or style of the video.

Items: 1–9
Each item is a public https:// URL. For a local file, upload it first with POST /v1/files and pass the returned data.url.

  • Images are used in list order; refer to them in the prompt by position.

If the value is wrong

  • More than the maximum: "reference_images" accepts at most 9 items
  • Combined with images: Cannot combine "images" with reference inputs in one task

reference_videos string[] Optional

Videos to take motion, camera work or content from.

Items: 1–3
Each item is a public https:// URL. For a local file, upload it first with POST /v1/files and pass the returned data.url.

  • Each link must return an MP4 or MOV file whose host allows byte-range requests: the gateway reads the length of every clip before creating the task, because reference seconds are billed.
  • Each clip runs 1.8 to 15 seconds and all clips together at most 15 seconds.

Reference videos add to the price for every second they run (see Billing). Trim them to the part you need.

If the value is wrong

  • More than the maximum: "reference_videos" accepts at most 3 items
  • The clip cannot be read: A reference video could not be read: reference_videos[0]: its host does not allow byte-range requests. Send an MP4 or MOV file at a public HTTPS URL whose host allows byte-range requests.

reference_audios string[] Optional

Music, voice or sound to follow. Audio cannot be the only reference: send at least one reference image or video with it.

Items: 1–3
Each item is a public https:// URL. For a local file, upload it first with POST /v1/files and pass the returned data.url.

  • WAV and MP3 clips are measured against the limits below; other formats are passed to the model unmeasured.

If the value is wrong

  • More than the maximum: "reference_audios" accepts at most 3 items
  • Audio without any reference image or video: seedance-2-mini audio reference requires at least one reference image or video

duration integer OptionalDefault: 5

Length of the video in seconds, a whole number.

Default: 5
Range: 4–15

  • If you leave it out, 5 is sent.

If the value is wrong

  • Outside the range or not a whole number: "duration" is outside its supported range

aspect_ratio string OptionalDefault: adaptive

Shape of the video as width:height. adaptive lets the model choose from the inputs.

Allowed values: adaptive, 21:9, 16:9, 4:3, 1:1, 3:4, 9:16
Default: adaptive

  • With adaptive the reservation assumes the largest frame of the chosen resolution, so it can be slightly higher than with a fixed ratio.

If the value is wrong

  • A value not in the list: "aspect_ratio" must be one of: [adaptive 21:9 16:9 4:3 1:1 3:4 9:16]

resolution string OptionalDefault: 720p

Output resolution, 480p or 720p. 720p costs more per second.

Allowed values: 480p, 720p
Default: 720p

  • Lower case only. 1080p and 4K are not available on this model (use seedance-2).

If the value is wrong

  • A value not in the list (for example 1080p or 720P): "resolution" must be one of: [480p 720p]

The gateway also checks these combinations before creating the task:

  • images cannot be combined with reference inputs

Input media limits

The gateway reads every input before the task is created and refuses one outside these limits with a 400 bad_request that names the input. Nothing is charged.

MediaLimits checked before the task is created
Imageswidth and height 300–6000 px; aspect ratio (width ÷ height) 0.4–2.5; at most 30 MB each
Videoseach 1.8–15 s; 15 s in total; at least 407,696 pixels per frame (width × height); 24–60 FPS
Audioeach 2–15 s; 15 s in total
  • Reference videos must be MP4 or MOV, at a public HTTPS link whose host answers byte-range requests. A clip whose length cannot be read is always refused, because its seconds are billed.
  • Image size is checked when the host reports it. Use JPEG, PNG or WebP; a file the model cannot use fails the task after submission with bad_request, and the task is refunded.
  • Limits are reported in the order length, sides, aspect ratio, pixels, frame rate and size. The message names the input by list and position, counting from 0 like the field errors: reference_videos[0] is 1.5 seconds long; this model takes reference video of 1.8 to 15 seconds.
  • Lengths are measured with a 0.1-second tolerance. Sizes are checked only when the host reports them.
  • Image and audio links are refused at create only when the host answers with a 4xx error or returns an empty file, for example images[1] could not be downloaded: the URL returned HTTP 404.; other problems with them surface after submission.
  • A clip at 23.976 FPS counts as below 24 and is refused; re-export it at 24 FPS or higher.
  • Have a local file? Upload it with POST /v1/files and pass the returned data.url.

Combination rules

These are checked when the task is created, in this order. A request that breaks one is refused with 400 bad_request and costs nothing.

RequestRefused with
images together with any reference_* fieldCannot combine "images" with reference inputs in one task
reference_audios without a reference image or videoseedance-2-mini audio reference requires at least one reference image or video

Fields this model does not accept

Sending one of these is refused before anything is charged, instead of being ignored:

  • Fields of other video models, such as generate_audio (not offered on Mini), seed, task_type, output_format (Seedance 2.5 only), watermark, quality, sound, multi_shots or character_orientation → field "generate_audio" is not supported by model seedance-2-mini (with the field you sent).
  • A name no BeatAPI video model uses → unknown field: <name>.

Estimating the price

The video tokens of a task are N = W × H × (24 × D + 1 + 24 × R) / 1024, where W × H is the frame size in pixels at the chosen resolution and aspect ratio (1280 × 720 for 720p at 16:9, 864 × 496 for 480p at 16:9), D is the output length in seconds and R the total length of the reference videos in seconds (0 without any). The price is N times the rate per million video tokens: about 3.466withoutreferencevideoand3.466 without reference video and 2.110 with it, for 480p and 720p alike.

For example, 5 seconds at 720p and 16:9 without reference video is 1280 × 720 × 121 / 1024 = 108,900 tokens, about $0.377. The gateway measures the reference clips itself; you do not send their length. This is an estimate; usage on the task shows what was reserved and charged.

Request examples

curl --request POST \
--url https://api.beatapi.io/v1/videos/tasks \
--header "Authorization: Bearer $BEATAPI_API_KEY" \
--header 'Content-Type: application/json' \
--data '{
"model": "seedance-2-mini",
"prompt": "A handheld tracking shot through a rain-lit night market, neon reflections on wet stone",
"duration": 5,
"aspect_ratio": "16:9",
"resolution": "720p"
}'

Text to video

A 5-second 720p landscape clip.

curl --request POST \
--url https://api.beatapi.io/v1/videos/tasks \
--header "Authorization: Bearer $BEATAPI_API_KEY" \
--header 'Content-Type: application/json' \
--data '{
"model": "seedance-2-mini",
"prompt": "A handheld tracking shot through a rain-lit night market, neon reflections on wet stone",
"duration": 5,
"aspect_ratio": "16:9",
"resolution": "720p"
}'

First frame

The video starts from the image.

curl --request POST \
--url https://api.beatapi.io/v1/videos/tasks \
--header "Authorization: Bearer $BEATAPI_API_KEY" \
--header 'Content-Type: application/json' \
--data '{
"model": "seedance-2-mini",
"prompt": "Animate the singer with a quick natural camera push-in",
"images": [
"https://media.beatapi.io/samples/neon-singer.png"
],
"duration": 5,
"resolution": "720p"
}'

First and last frame

The video moves from the first image to the second.

curl --request POST \
--url https://api.beatapi.io/v1/videos/tasks \
--header "Authorization: Bearer $BEATAPI_API_KEY" \
--header 'Content-Type: application/json' \
--data '{
"model": "seedance-2-mini",
"prompt": "The camera pushes in from the bottle on the table to the singer on a neon stage in one continuous move",
"images": [
"https://media.beatapi.io/samples/smart-bottle.png",
"https://media.beatapi.io/samples/neon-singer.png"
],
"duration": 6,
"resolution": "720p"
}'

Image and audio references

A performance that follows a character image and a music clip.

curl --request POST \
--url https://api.beatapi.io/v1/videos/tasks \
--header "Authorization: Bearer $BEATAPI_API_KEY" \
--header 'Content-Type: application/json' \
--data '{
"model": "seedance-2-mini",
"prompt": "The singer from the first reference image performs on stage in time with the reference music, warm spotlights, slow orbiting camera",
"reference_images": [
"https://media.beatapi.io/samples/neon-singer.png"
],
"reference_audios": [
"https://media.beatapi.io/samples/neon-singer-preview.mp3"
],
"duration": 8,
"resolution": "720p"
}'

Image, video and audio references

Replace the video link with your own MP4 or MOV of 15 seconds or less. Every second of the reference video is billed (see Billing).

curl --request POST \
--url https://api.beatapi.io/v1/videos/tasks \
--header "Authorization: Bearer $BEATAPI_API_KEY" \
--header 'Content-Type: application/json' \
--data '{
"model": "seedance-2-mini",
"prompt": "A product film: the bottle from the first reference image on a turntable, camera movement like the first reference video, cut to the beat of the reference music",
"reference_images": [
"https://media.beatapi.io/samples/smart-bottle.png"
],
"reference_videos": [
"https://your-cdn.example.com/clips/source.mp4"
],
"reference_audios": [
"https://media.beatapi.io/samples/neon-singer-preview.mp3"
],
"duration": 8,
"resolution": "720p"
}'

Responses

Create a task (201)

The task object. output is null until the task succeeds. Fields marked “while running” disappear once the task finishes.

{
"data": {
"id": "task_7Qm2Xc9LpR4vT8sKa1Nf6YbH3eWdJ0uZ",
"object": "task",
"task_kind": "video",
"capability_id": "seedance-2-mini",
"capability_version": 1,
"media_type": "video",
"model": "seedance-2-mini",
"status": "queued",
"stage": "queued",
"created_at": 1791993600,
"updated_at": 1791993600,
"completed_at": null,
"poll_after_seconds": 8,
"output": null,
"usage": {
"credits_reserved": 0.377421,
"credits_settled": 0,
"credits_refunded": 0,
"credits_charged": 0.377421,
"billable_duration_seconds": 5
},
"request_id": "req_5f0c2a9e4b7d4e31",
"error_code": null,
"error_message": null
}
}
FieldTypeDescription
data.idstringTask ID: task_ followed by 32 letters and digits. Use it to poll and to match webhook events.
data.objectstringAlways task.
data.task_kindstringimage or video.
data.capability_idstringThe model ID you sent.
data.capability_versionintegerContract version of the model, currently 1.
data.media_typestringimage or video.
data.modelstringThe model ID you sent (same as capability_id).
data.statusstringqueued, processing, succeeded or failed. Only the last two are final.
data.stagestringRepeats status; kept for older clients.
data.created_atintegerWhen the task was created, Unix seconds.
data.updated_atintegerLast change, Unix seconds.
data.completed_atinteger | nullWhen the task finished, Unix seconds; null while it runs.
data.poll_after_secondsintegerWhile running: how long to wait before the next poll (5 for images, 8 for videos).
data.typical_secondsobjectWhile running, when enough recent tasks exist: p50 and p90 completion times in seconds over the last window, from samples tasks.
data.outputobject | nullThe result; null until status is succeeded. See the output fields below.
data.usage.credits_reservednumberUSD held from your balance when the task was created.
data.usage.credits_chargednumberUSD this task costs; 0 on a failed task.
data.usage.credits_settlednumberUSD finally taken; set when the task succeeds, otherwise 0.
data.usage.credits_refundednumberUSD returned to your balance; equals the reservation on a failed task once the refund is recorded.
data.usage.billable_duration_secondsintegerVideo only: the seconds the price is based on. Absent when the model reports no duration.
data.request_idstringRequest ID. Include it when you contact support.
data.error_codestring | nullFailure code; null unless the task failed.
data.error_messagestring | nullWhat went wrong and what to change; null unless the task failed.

Finished task

GET /v1/tasks/{task_id} returns HTTP 200 with status: "succeeded" and the result in data.output.

{
"data": {
"id": "task_7Qm2Xc9LpR4vT8sKa1Nf6YbH3eWdJ0uZ",
"object": "task",
"task_kind": "video",
"capability_id": "seedance-2-mini",
"capability_version": 1,
"media_type": "video",
"model": "seedance-2-mini",
"status": "succeeded",
"stage": "succeeded",
"created_at": 1791993600,
"updated_at": 1791993690,
"completed_at": 1791993690,
"output": {
"media": [
{
"type": "video",
"url": "https://media.beatapi.io/outputs/task_7Qm2Xc9LpR4vT8sKa1Nf6YbH3eWdJ0uZ/0.mp4",
"mime_type": "video/mp4"
}
],
"r2_url": "https://media.beatapi.io/outputs/task_7Qm2Xc9LpR4vT8sKa1Nf6YbH3eWdJ0uZ/0.mp4"
},
"usage": {
"credits_reserved": 0.377421,
"credits_settled": 0.377421,
"credits_refunded": 0,
"credits_charged": 0.377421,
"billable_duration_seconds": 5
},
"request_id": "req_5f0c2a9e4b7d4e31",
"error_code": null,
"error_message": null
}
}

Output fields

FieldTypeDescription
output.mediaobject[]The generated files; one video for this model.
output.media[].typestringAlways video.
output.media[].urlstringHTTPS link to the stored video. Download and keep it; no retention period is promised.
output.media[].mime_typestringAlways video/mp4.
output.r2_urlstringThe video URL again, for older clients. Read media instead.

Failed task

A failed task is still HTTP 200 on GET /v1/tasks/{task_id}: the failure is in the body. The reservation is returned in full, so nothing is charged.

{
"data": {
"id": "task_7Qm2Xc9LpR4vT8sKa1Nf6YbH3eWdJ0uZ",
"object": "task",
"task_kind": "video",
"capability_id": "seedance-2-mini",
"capability_version": 1,
"media_type": "video",
"model": "seedance-2-mini",
"status": "failed",
"stage": "failed",
"created_at": 1791993600,
"updated_at": 1791993690,
"completed_at": 1791993690,
"output": null,
"usage": {
"credits_reserved": 0.377421,
"credits_settled": 0,
"credits_refunded": 0.377421,
"credits_charged": 0,
"billable_duration_seconds": 5
},
"retryable": true,
"request_id": "req_5f0c2a9e4b7d4e31",
"error_code": "processing_failed",
"error_message": "The task failed during processing on our side. Retry; a failed task is refunded."
}
}
FieldTypeDescription
data.error_codestringOne of bad_request and content_policy_violation (change the request) or processing_unavailable, processing_timeout, processing_failed and result_transfer_failed (try again later). See Errors.
data.error_messagestringA sentence that names the problem and the fix.
data.retryablebooleanPresent only on a failed task: true when the same request can succeed if you send it again.
data.usageobjectOnce the refund is recorded (normally at the moment the task fails): credits_charged and credits_settled are 0, and credits_refunded equals credits_reserved.

Complete example

Create a task, wait for it with the server’s polling hint, and print the result URLs. Set BEATAPI_API_KEY in your environment and install requests.

import os
import time
import uuid
import requests
API = "https://api.beatapi.io"
HEADERS = {"Authorization": f"Bearer {os.environ['BEATAPI_API_KEY']}"}
def create_task(body: dict) -> dict:
# One Idempotency-Key per logical request: a retry with the same key cannot create a second task.
headers = {**HEADERS, "Idempotency-Key": str(uuid.uuid4())}
for attempt in range(3):
response = requests.post(f"{API}/v1/videos/tasks", headers=headers, json=body, timeout=60)
if response.status_code in (429, 503) and attempt < 2:
time.sleep(int(response.headers.get("Retry-After", 10)))
continue
break
try:
payload = response.json()
except ValueError: # an edge error page is not JSON
response.raise_for_status()
raise
if not response.ok:
error = payload["error"]
raise RuntimeError(f"{response.status_code} {error['code']}: {error['message']} (request_id={error.get('request_id')})")
return payload["data"]
def wait_for_task(task_id: str, timeout_seconds: int = 1800) -> dict:
deadline = time.monotonic() + timeout_seconds
while time.monotonic() < deadline:
response = requests.get(f"{API}/v1/tasks/{task_id}", headers=HEADERS, timeout=30)
if response.status_code == 429 or response.status_code >= 500:
time.sleep(int(response.headers.get("Retry-After", 10)))
continue
response.raise_for_status()
task = response.json()["data"]
if task["status"] in ("succeeded", "failed"):
return task
time.sleep(task.get("poll_after_seconds", 5))
raise TimeoutError(f"task {task_id} is still running; keep polling later")
task = create_task({
"model": "seedance-2-mini",
"prompt": "A handheld tracking shot through a rain-lit night market, neon reflections on wet stone",
"duration": 5,
"aspect_ratio": "16:9",
"resolution": "720p"
})
print("created", task["id"])
task = wait_for_task(task["id"])
if task["status"] == "failed":
raise SystemExit(f"{task['error_code']}: {task['error_message']}")
for item in task["output"]["media"]:
print(item["url"])

Billing

  • The price follows the size and length of the video: more seconds, a higher resolution or a larger frame cost more. Reference images and audio add nothing.
  • Without reference video, a 16:9 clip costs about 0.035(480p)or0.035 (480p) or 0.075 (720p) per second. Other aspect ratios differ by a few percent.
  • With reference_videos, the whole request moves to the lower “with video input” rate, and every second of reference video counts like a second of output: about 0.021(480p)or0.021 (480p) or 0.046 (720p) per second of output plus reference, at 16:9.
  • The table below shows 8-second clips; its “with video input” rows include an 8-second reference video.
  • The price is reserved when the task is created. With adaptive the reservation assumes the largest frame of the resolution. You pay the reservation, or the actual amount if the delivered video comes to more.
  • A failed task, including one refused by moderation after submission, is refunded in full.

Current list prices, the same as on Pricing. An account with a negotiated discount pays less; data.usage on the task always shows the amount actually charged.

OptionList price (USD)
8 sec · 480p · no video input$0.279931
8 sec · 480p · with video input$0.339902
8 sec · 720p · no video input$0.602001
8 sec · 720p · with video input$0.730973

Common errors

Error or symptomCauseFix
400 resolution "720p" is not available for this model right now; available: …No line serving this model accepts that value at the moment; the same can happen for aspect_ratio.Use one of the listed values, or retry later.
400 field "generate_audio" is not supported by model seedance-2-miniA field of another video model that this model does not accept (generate_audio, seed, task_type, output_format, watermark, quality, sound, multi_shots, character_orientation).Remove the field. generate_audio is available on Seedance 2.0, 2.0 Fast and 2.5; seed, task_type and output_format only on 2.5.
400 "resolution" must be one of: [480p 720p]1080p, 4k, 720P or another value.Send 480p or 720p; for 1080p or 4K use seedance-2.
400 seedance-2-mini audio reference requires at least one reference image or videoreference_audios sent alone.Add a reference image or video.
400 Cannot combine "images" with reference inputs in one taskFrames and reference_* in the same request.Use frames or references. For several pictures, put them all in reference_images.
400 "duration" is outside its supported rangeNot a whole number from 4 to 15, or sent as a string.Send an integer such as 5.
400 A reference video could not be read: reference_videos[0]: …Not an MP4 or MOV, a host without byte-range support, a 404, or an empty file.Host the clip on public HTTPS storage that supports range requests, or upload it with POST /v1/files.
400 reference_videos[0] is 1.5 seconds long; this model takes reference video of 1.8 to 15 seconds.A reference clip is shorter or longer than the limit.Trim or replace the clip.
400 The reference videos run 20 seconds in total; this model takes at most 15.The reference clips together are too long.Trim or drop clips.
Task failed with content_policy_violationThe prompt, an input or the result was refused by moderation (real people, public figures, copyrighted characters).Change the input. Retrying unchanged fails again; nothing is charged.
402 insufficient_creditsThe balance is below the reservation; long reference videos and adaptive raise it.Top up, shorten the references, or pick a fixed aspect_ratio.

HTTP errors at a glance

Errors before a task exists arrive as a non-2xx response, and nothing is charged. Branch on error.code or error.retryable; message names the problem. The full list and retry policy are on Errors.

{
"error": {
"code": "bad_request",
"message": "\"prompt\" is required",
"retryable": false,
"request_id": "req_5f0c2a9e4b7d4e31"
}
}
HTTP statuserror.codeWhat to do
400bad_request, content_policy_violationFix the request; the message names the field. Do not retry unchanged.
401missing_api_key, invalid_api_key (older clients may see unauthorized)Send a valid key as Authorization: Bearer <key>.
402insufficient_creditsTop up, or raise the key’s quota, then send it again.
403forbiddenThe key or account may not use this model (for example, free credit only covers some models). Do not retry unchanged.
404not_foundOn GET /v1/tasks/{task_id}: the task does not exist for this key’s account. Check the ID.
409idempotency_conflictUse a new Idempotency-Key, or wait for the first request with this key to finish.
429rate_limit_exceededWait Retry-After seconds (also error.retry_after_seconds), then retry.
500internal_errorRetry with backoff; contact support with request_id if it continues.
503processing_unavailable, processing_timeout, processing_failed, result_transfer_failedNothing was charged. Retry with exponential backoff.

Authentication

AuthorizationBearer

Send your API key as Authorization: Bearer <BEATAPI_API_KEY>.

Headers

Idempotency-KeystringOptional<=255 characters

Send the body as JSON with Content-Type: application/json. Idempotency-Key is optional: send a unique value (at most 255 characters) per logical request and reuse it only to retry that exact body. Within 24 hours a retry with the same key and body returns the first response again with Idempotent-Replayed: true; the same key with a different body returns 409 idempotency_conflict. Responses other than 2xx are not stored, so a retry after a 400 or 402 runs again.

Request

This endpoint expects an object.
modelenumRequired

The model to run.

Value: seedance-2-mini

If the value is wrong

  • Missing: "model" is required
  • An image model sent to this endpoint: "model" nano-banana-2 is served by POST /v1/images/tasks, not this endpoint
Allowed values:
promptstringRequired1-5000 characters

What happens in the video: subject, action, camera movement, style and sound. With references, say what each input is for.

Length: 1–5000 characters

  • Length is counted in characters (a CJK character counts as one).
  • Refer to inputs by their position, for example “the first reference image” or “the second reference video”.

If the value is wrong

  • Missing: "prompt" is required
  • Empty or longer than the limit: "prompt" has an unsupported length
aspect_ratioenumOptionalDefaults to adaptive

Shape of the video as width:height. adaptive lets the model choose from the inputs.

Allowed values: adaptive, 21:9, 16:9, 4:3, 1:1, 3:4, 9:16

Default: adaptive

  • With adaptive the reservation assumes the largest frame of the chosen resolution, so it can be slightly higher than with a fixed ratio.

If the value is wrong

  • A value not in the list: "aspect_ratio" must be one of: [adaptive 21:9 16:9 4:3 1:1 3:4 9:16]
durationintegerOptional4-15Defaults to 5

Length of the video in seconds, a whole number.

Default: 5

Range: 4–15

  • If you leave it out, 5 is sent.

If the value is wrong

  • Outside the range or not a whole number: "duration" is outside its supported range
imageslist of stringsOptional

A first frame, or a first and a last frame.

Items: 1–2

Each item is a public https:// URL. For a local file, upload it first with POST /v1/files and pass the returned data.url.

  • One link: the video starts from this image. Two links: images[0] is the first frame and images[1] the last.
  • For more pictures, or pictures that guide the video without being frames, use reference_images instead.

If the value is wrong

  • More than two links: "images" accepts at most 2 items
  • Combined with any reference_* field: Cannot combine "images" with reference inputs in one task
  • Not an https:// link: "images[0]" must be a public HTTPS URL
reference_audioslist of stringsOptional

Music, voice or sound to follow. Audio cannot be the only reference: send at least one reference image or video with it.

Items: 1–3

Each item is a public https:// URL. For a local file, upload it first with POST /v1/files and pass the returned data.url.

  • WAV and MP3 clips are measured against the limits below; other formats are passed to the model unmeasured.

If the value is wrong

  • More than the maximum: "reference_audios" accepts at most 3 items
  • Audio without any reference image or video: seedance-2-mini audio reference requires at least one reference image or video
reference_imageslist of stringsOptional

Pictures that guide the content, characters, products or style of the video.

Items: 1–9

Each item is a public https:// URL. For a local file, upload it first with POST /v1/files and pass the returned data.url.

  • Images are used in list order; refer to them in the prompt by position.

If the value is wrong

  • More than the maximum: "reference_images" accepts at most 9 items
  • Combined with images: Cannot combine "images" with reference inputs in one task
reference_videoslist of stringsOptional

Videos to take motion, camera work or content from.

Items: 1–3

Each item is a public https:// URL. For a local file, upload it first with POST /v1/files and pass the returned data.url.

  • Each link must return an MP4 or MOV file whose host allows byte-range requests: the gateway reads the length of every clip before creating the task, because reference seconds are billed.
  • Each clip runs 1.8 to 15 seconds and all clips together at most 15 seconds.

Notes: Reference videos add to the price for every second they run (see Billing). Trim them to the part you need.

If the value is wrong

  • More than the maximum: "reference_videos" accepts at most 3 items
  • The clip cannot be read: A reference video could not be read: reference_videos[0]: its host does not allow byte-range requests. Send an MP4 or MOV file at a public HTTPS URL whose host allows byte-range requests.
resolutionenumOptionalDefaults to 720p

Output resolution, 480p or 720p. 720p costs more per second.

Allowed values: 480p, 720p

Default: 720p

  • Lower case only. 1080p and 4K are not available on this model (use seedance-2).

If the value is wrong

  • A value not in the list (for example 1080p or 720P): "resolution" must be one of: [480p 720p]
Allowed values:

Response

The task object. output is null until the task succeeds. Fields marked “while running” disappear once the task finishes.

Errors

400
Bad Request Error
401
Unauthorized Error
402
Payment Required Error
403
Forbidden Error
409
Conflict Error
429
Too Many Requests Error
500
Internal Server Error
503
Service Unavailable Error