MiniMax H3 Max
Generate videos of 5 seconds or more at 480P or 768P from text or one or two frames, priced per second.
- Asynchronous: the create call returns a task ID; the video arrives when the task succeeds.
- Three ways in: text only, a first frame, or a first and last frame. There are no reference inputs and no
aspect_ratio. - Two resolutions: 480P and 768P (the default), written in upper case.
- Billed per second of video at the rate of the chosen resolution;
durationstarts at 5 seconds. A failed task costs nothing.
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
Five MiniMax H3 models share this endpoint but not the same inputs. The values below come straight from the gateway contract.
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
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.
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.
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
Request parameters
model
string
Required
The model to run.
Value: minimax-h3-max
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 shot: the motion, the expression, the camera and the style.
Length: 1–5000 characters
- Length is counted in characters (a CJK character counts as one).
- With frames, describe how the video gets from one to the other, or what moves after the first frame.
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 andimages[1]the last. - Reference images are not accepted on this model (
reference_imagesis refused).
If the value is wrong
- More than two links:
"images" accepts at most 2 items - Not an https:// link:
"images[0]" must be a public HTTPS URL
duration
integer
OptionalDefault: 5
Length of the video in seconds, a whole number of at least 5.
Default: 5
Range: ≥ 5
- If you leave it out,
5is used. - The price follows this value (see Billing).
If the value is wrong
- Below 5 seconds, or not a whole number:
"duration" is outside its supported range
resolution
string
OptionalDefault: 768P
Output resolution. 768P costs more per second than 480P.
Allowed values: 480P, 768P
Default: 768P
- Upper case only:
768pis refused. - 1080P and 2K are not offered here;
minimax-h3-normalhas 1080p andminimax-h3-fasthas 2K.
If the value is wrong
- A value not in the list (for example
768p,1080Por2K):"resolution" must be one of: [480P 768P]
seed
integer
Optional
A fixed number to seed the generation. Leave it out for a random seed.
Range: ≥ 0
- A whole number of at least 0.
If the value is wrong
- Negative or not a whole number:
"seed" is outside its supported range
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.
- Only images are accepted on this model, so only the image row applies; the video and audio rows are shared by the H3 models and do not apply here.
- Images are checked in the order you sent them. Limits are checked in the order sides, aspect ratio. The message names the input by list and position, counting from 0 like the field errors:
images[0] is 200x200 pixels; this model takes images 256 to 5760 pixels on each side. - A link is refused at create only when its host answers with an HTTP 4xx error or returns an empty file, for example
images[1] could not be downloaded: the URL returned HTTP 404.; other problems with an input surface after submission and fail the task (refunded). - Have a local file? Upload it with
POST /v1/filesand pass the returneddata.url.
Fields this model does not accept
Sending one of these is refused before anything is charged, instead of being ignored:
aspect_ratio,reference_images,reference_videos,reference_audios,generate_audio,watermark,quality,soundand any other field from other video models →field "aspect_ratio" is not supported by model minimax-h3-max(with the field you sent).- Any other unknown field →
unknown field: <name>.
For reference inputs use minimax-h3-fast (images, videos and audio) or minimax-h3-normal (images and one video).
Request examples
Text to video
A 5-second 768P clip.
First frame
The video starts from the image.
First and last frame
The video moves from the first image to the second, at 480P with a fixed seed.
Responses
Create a task (201)
The task object. output is null until the task succeeds. Fields marked “while running” disappear once the task finishes.
Finished task
GET /v1/tasks/{task_id} returns HTTP 200 with status: "succeeded" and the result in data.output.
Output fields
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.
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.
Billing
- Billed per second of video: the requested
durationtimes the rate of the chosen resolution, which is about 0.08 per second at 768P. The list prices below are for 8 seconds. - The same request on
minimax-h3-max-turbocosts half as much. - The number of frames and
seeddo not change the price. - The price is reserved when the task is created;
usage.billable_duration_secondson the task shows the seconds billed. - 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.
Common errors
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.
Authentication
Send your API key as Authorization: Bearer <BEATAPI_API_KEY>.
Headers
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
The model to run.
Value: minimax-h3-max
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
What happens in the shot: the motion, the expression, the camera and the style.
Length: 1–5000 characters
- Length is counted in characters (a CJK character counts as one).
- With frames, describe how the video gets from one to the other, or what moves after the first frame.
If the value is wrong
- Missing:
"prompt" is required - Empty or longer than the limit:
"prompt" has an unsupported length
Length of the video in seconds, a whole number of at least 5.
Default: 5
Range: ≥ 5
- If you leave it out,
5is used. - The price follows this value (see Billing).
If the value is wrong
- Below 5 seconds, or not a whole number:
"duration" is outside its supported range
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 andimages[1]the last. - Reference images are not accepted on this model (
reference_imagesis refused).
If the value is wrong
- More than two links:
"images" accepts at most 2 items - Not an https:// link:
"images[0]" must be a public HTTPS URL
Output resolution. 768P costs more per second than 480P.
Allowed values: 480P, 768P
Default: 768P
- Upper case only:
768pis refused. - 1080P and 2K are not offered here;
minimax-h3-normalhas 1080p andminimax-h3-fasthas 2K.
If the value is wrong
- A value not in the list (for example
768p,1080Por2K):"resolution" must be one of: [480P 768P]
A fixed number to seed the generation. Leave it out for a random seed.
Range: ≥ 0
- A whole number of at least 0.
If the value is wrong
- Negative or not a whole number:
"seed" is outside its supported range
Response
The task object. output is null until the task succeeds. Fields marked “while running” disappear once the task finishes.

