Kling 4.0
Kling 4.0 costs $0.171/s (720p) on FairStack · a text to video model for Long cinematic shots, Widescreen 21:9 scenes, Social video in 9:16. No subscription required. Pay per generation with full REST API access. FairStack applies a transparent 20% margin on infrastructure cost so you always see the real price.
What is Kling 4.0?
Kling 4.0 is Kling AI's fourth-generation video model, released in October 2026. This key runs it as text-to-video: describe the shot and get a clip of any whole-second length from 3 to 30 seconds, at 720p or 1080p, in 16:9, 9:16, 1:1 or 21:9. The jump over Kling 3.0 is length and framing: runs up to 30 seconds (3.0 stopped at 15) and a cinematic 21:9 frame. For frame-by-frame control use Kling 4.0 Keyframes; to steer the shot with reference images, clips, characters or voices use Kling 4.0 Reference. Priced per second of output at the resolution you pick: the provider's rate plus a flat 20% platform fee, shown before you spend.
Key Features
What are Kling 4.0's strengths?
What are Kling 4.0's limitations?
What is Kling 4.0 best for?
How much does Kling 4.0 cost?
How does Kling 4.0 perform across capabilities?
Estimated from the Kling 4.0 launch notes, not benchmark-verified (PRD-1229)
How do I use the Kling 4.0 API?
curl -X POST https://api.fairstack.ai/v1/generations/video \
-H "Authorization: Bearer $FAIRSTACK_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "kling-4-0-t2v",
"input": {
"prompt": "Your prompt here"
}
}'import os
import requests
response = requests.post(
"https://api.fairstack.ai/v1/generations/video",
headers={
"Authorization": f"Bearer {os.environ['FAIRSTACK_API_KEY']}",
"Content-Type": "application/json",
},
json={
"model": "kling-4-0-t2v",
"input": {
"prompt": "Your prompt here"
}
},
)
result = response.json()
print(result["data"])const response = await fetch("https://api.fairstack.ai/v1/generations/video", {
method: "POST",
headers: {
Authorization: `Bearer ${process.env.FAIRSTACK_API_KEY}`,
"Content-Type": "application/json",
},
body: JSON.stringify({
"model": "kling-4-0-t2v",
"input": {
"prompt": "Your prompt here"
}
}),
});
const result = await response.json();
console.log(result.data);What parameters does Kling 4.0 support?
Frequently Asked Questions
How much does Kling 4.0 cost?
Kling 4.0 costs $0.171/s (720p) on FairStack as of 2026-11-10. This price includes FairStack's transparent 20% margin on infrastructure cost. No subscription or monthly fee — you pay per generation only. Minimum deposit is $1.
What is Kling 4.0 and what is it best for?
Kling 4.0 is Kling AI's fourth-generation video model, released in October 2026. This key runs it as text-to-video: describe the shot and get a clip of any whole-second length from 3 to 30 seconds, at 720p or 1080p, in 16:9, 9:16, 1:1 or 21:9. The jump over Kling 3.0 is length and framing: runs up to 30 seconds (3.0 stopped at 15) and a cinematic 21:9 frame. For frame-by-frame control use Kling 4.0 Keyframes; to steer the shot with reference images, clips, characters or voices use Kling 4.0 Reference. Priced per second of output at the resolution you pick: the provider's rate plus a flat 20% platform fee, shown before you spend. Kling 4.0 is best for Long cinematic shots, Widescreen 21:9 scenes, Social video in 9:16. Available via FairStack's REST API with curl, Python, and Node.js SDKs.
Does Kling 4.0 have an API?
Yes. Kling 4.0 is available via FairStack's REST API at api.fairstack.ai. Send a POST request to /v1/generations/video with your API key, the model key, and an input object (input.prompt). Works with curl, Python requests, Node.js fetch, and any HTTP client. No SDK installation required.
How does Kling 4.0 compare to other video models?
Kling 4.0 excels at Long cinematic shots, Widescreen 21:9 scenes, Social video in 9:16. It is a text to video model priced at $0.171/s (720p) on FairStack. Key strengths: Long single takes (up to 30s), Cinematic 21:9 framing. Compare all video models at fairstack.ai/models.