API Overview

How it works

The kling-4.ai API is a small REST surface around one idea: you create a generation job, then poll it until the video is ready.

POST /api/ai-video/jobs          create a generation job
GET  /api/ai-video/jobs/{id}     fetch one job (refreshes provider status)
GET  /api/ai-video/jobs          list your recent jobs
POST /api/ai-video/jobs/sync     refresh all of your active jobs at once

• Base URL: https://kling-4.ai
• Auth: an approved API key in the x-api-key header — see Authentication
• Format: JSON in, JSON out
• Model: the job's model field selects the Kling model — see Models. Website access to Kling 4.0 does not imply API access. This legacy endpoint does not accept kling-v4; use only documented model identifiers.

Quick start

1. Get a key. API key access is rolling out during v1. Contact us if you need server-side access.

2. Create a job:

curl -X POST 'https://kling-4.ai/api/ai-video/jobs' \
  -H 'x-api-key: YOUR_API_KEY' \
  -H 'Content-Type: application/json' \
  -d '{
    "model": "kling-v2-6",
    "prompt": "A cinematic sunrise over a glass city, slow drone push-in",
    "parameters": {
      "mode": "std",
      "duration": 5,
      "aspectRatio": "16:9"
    }
  }'

The response contains the job you'll poll:

{
  "job": {
    "id": "0b6c2f6e-6d5f-4a4e-9d3e-7c9a1f2b8d41",
    "model": "kling-v2-6",
    "status": "queued",
    "progress": 0,
    "resultUrl": null,
    "createdAt": "2026-07-09T03:12:45.000Z"
  }
}

3. Poll until it completes:

curl 'https://kling-4.ai/api/ai-video/jobs/0b6c2f6e-6d5f-4a4e-9d3e-7c9a1f2b8d41' \
  -H 'x-api-key: YOUR_API_KEY'

When status becomes completed, the job carries a resultUrl (the video file) and a thumbnailUrl. Renders typically take a few minutes; polling every 10–15 seconds is plenty. Note that resultUrl links expire — check resultExpiresAt and download your file promptly.

Runnable Node.js and Python versions of this flow live in our awesome-kling-4 repo on GitHub, alongside a tested prompt library.

Endpoints at a glance

Quotas

Browser guests can explicitly claim a one-time image credit reward. Video generation requires sign-in. Eligible signed-in users receive a first-sign-in reward instead of that day’s daily reward, then daily rewards on later UTC dates. Each generation must fit the server quote and applicable free-cost limits. Approved API keys use the credits or quota assigned to that workspace. See Errors for insufficient-credit and request validation responses; for higher volume, contact us.