FLUX.3 is Black Forest Labs' frontier video model. This endpoint continues an existing clip beyond its final frame, generating additional footage that stays consistent with the original motion and scene.
Flux 3 Extend Video (blackforestlabs/flux-3/extend-video) is a video model from Blackforestlabs. Pricing via AIgateway: $0.205 per second. Call it via https://api.aigateway.sh/v1/videos/generations — set model="blackforestlabs/flux-3/extend-video".
curl https://api.aigateway.sh/v1/videos/generations \
-H "Authorization: Bearer $AIGATEWAY_API_KEY" \
-H "Content-Type: application/json" \
-d '{"model":"blackforestlabs/flux-3/extend-video","prompt":"a slow drone shot over a mountain lake"}'{
"model": "blackforestlabs/flux-3/extend-video",
"prompt": "A drone shot of a mountain lake at golden hour",
"duration": 5, // seconds
"aspect_ratio": "16:9"
}
// Response is an async job — poll /v1/jobs/<id> until status === "completed".{
"id": "job_abc123",
"status": "queued", // queued | processing | completed | failed
"model": "blackforestlabs/flux-3/extend-video",
"created": 1776947082
}
// After completion:
{
"id": "job_abc123",
"status": "completed",
"result": {
"url": "https://media.aigateway.sh/video/abc123.mp4",
"duration": 5,
"resolution": "1920x1080"
}
}# See docs at https://aigateway.sh/docs