MiniMax H3 API

Introduction

MiniMax H3 Image to video starts from an opening frame supplied in image_url and generates what happens next: 4 to 15 whole seconds at 768p or 2k, with sound generated in the same pass. An optional last_image_url gives the clip a closing frame to resolve to. There is no aspect-ratio field, because the opening frame sets the shape of the output.

Choose a MiniMax H3 mode by starting material

Key features

The opening frame decides the subject

The model follows the supplied frame closely, which makes this the most literal way to get the subject, wardrobe and room you designed. In the windowsill-turn example everything identifying, from the face to the nightgown to the rain-streaked window, comes from the image; the prompt only asks for an exhale, a neon pulse and a head turn. An opening frame that already shows the scene gets far closer to the brief than the same words typed into text-to-video.

An optional closing frame

last_image_url pins where the shot lands. The closing frame tightens the ending only. The middle of the clip is still generated freely, and the longer the clip, the further the motion can drift from the closing frame.

Duration, resolution and input limits

Duration runs from 4 to 15 whole seconds, but a 4-second clip is only available at 768p; 2k needs at least 5 seconds. Both resolutions are native. The opening frame must measure between 256 and 5,760 px on each side, keep an aspect ratio between 2:5 and 5:2, and stay under 30 MB.

Request parameters

Pricing

Prices are in credits, the same credits you use on the website (1 credit = $0.01). The hold is taken when the task is accepted and settled to the actual charge when it finishes; failed tasks are refunded.

Each task is rounded up to whole credits, so one run at the lowest tier costs 28 credits for a 5-second clip ($0.28).

For an exact number before you run, send the same body to POST /jobs/quote.

Use cases

Animate a still you have already approved

When a frame exists, whether a generated still or an authorised photograph, this endpoint turns it into motion without re-describing it. The prompt carries only the change (action, camera, sound), which keeps every word for what the image cannot say on its own.

Reveal what the frame does not show

The cup-then-two-in-one-shirt example opens on a still life. A hand lifts the cup out of frame, the camera tilts and racks focus, and a second figure appears deeper in the room: three changes, all temporal, none of them present in the input image. It ran for six seconds, a sensible draft length before a 2k run.

Continue a scene past 15 seconds

To carry a scene on, use MiniMax H3 Video extend: it opens the next segment on the final frame of the approved clip and returns the two joined in one file, so each prompt only has to describe what happens next. To steer the next shot frame by frame yourself, take that final frame and submit it here as the next image_url.

Prompt guide & pro tips

Do not re-describe the frame

Describe the change after the opening frame and leave appearance to the image. A quick check is that every clause should name something that moves or makes a sound. The windowsill-turn prompt, "she turns her head toward camera without changing expression. Rain runs down the window, distant traffic", is enough because the frame already shows who she is and where.

Keep the two frames continuous

When you send last_image_url, prepare it as a pair with the opening frame: same subject, same wardrobe, same light and a plausible change of framing. Two frames that disagree force the middle of the clip to negotiate between them.

Prepare the frame for the output

Because the frame sets the output shape, crop the still to the delivery aspect ratio before uploading and check it against the size limits. Draft at 768p, then re-run the take you want at 2k with at least five seconds of duration. Expect a new take rather than a frame-for-frame upscale, since the endpoint takes no seed.

API quick start

Call the MiniMax H3 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- and use the same credits as the website.
2. Send the request. POST /jobs/createTask with model minimax/h3/image-to-video 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": "minimax/h3/image-to-video",
  "input": {
    "prompt": "A slow aerial shot drifting over a misty pine forest at sunrise",
    "image_url": "https://media.popnow.ai/influencer/examples/marco.webp",
    "resolution": "768p",
    "duration_seconds": 5
  }
}'

# 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.

MiniMax H3 API questions

All MiniMax models

MiniMax H3 Max is the fast-generation variant, with an optional closing frame but no reference mode and no 2K. H3 is the all-rounder.

• MiniMax H3 APIExpressive clips with audio, up to 2KFrom 28 credits for a 5-second clip
• MiniMax Speech 2.8 HD APIHigh-fidelity speech in 400+ voices with emotion controlFrom 18 credits per 1,000 characters
• MiniMax Music 3.0 APIFinished stereo songs, with vocals or instrumentalFrom 27 credits per run
• MiniMax H3 Singularity LoRA APICommunity-tuned H3 video that loads your own LoRAsFrom 45 credits for a 5-second clip
• MiniMax H3 Max APIFast clips with ambience, effects and musicFrom 38 credits for a 5-second clip
• MiniMax H3 LoRA APIMiniMax H3 video with sound and up to three of your LoRAsFrom 38 credits for a 5-second clip
• MiniMax H3 Image LoRA APIH3 stills and edits with up to three of your LoRAsFrom 7 credits per image
• MiniMax Speech 2.8 Turbo APIFast speech in 400+ voices with emotion controlFrom 11 credits per 1,000 characters

Other video APIs

• Seedance 2.5 APIByteDance's newest: 30-second clips with native audioFrom 56 credits for a 5-second clip
• Kling 3.0 API4K clips, multi-shot cuts and motion controlFrom 51 credits for a 5-second clip
• Vidu Q4 Preview APIUp to 4K clips with sound and spoken dialogueFrom 34 credits for a 5-second clip
• Wan 3.0 APIUp to 30-second clips with synced audioFrom 34 credits for a 5-second clip
• Kling O3 APIKling’s unified model: create, animate, reference and edit up to 4KFrom 51 credits for a 5-second clip
• LTX 2.5 APILong 20-second takes up to 4K with a soundtrackFrom 68 credits for a 5-second clip

More about MiniMax H3

Try it

MiniMax H3 AI Video Generator onlineCreate videos with MiniMax H3 in PopNow

Compare

Kling 3.0 vs MiniMax H3

Docs

MiniMax H3 model ID and input schema in the API docsPopNow API quickstart: your first request in five minutesImage to video guide for the PopNow APIWebhooks: get MiniMax H3 results without polling