Kling 4.0 AI Video Generator: Make Cinematic Video from Text and Images

Kling 4.0 is Kuaishou's flagship AI video model, launching October 2026. It generates video from a text prompt, a single image, or up to 15 reference items, and renders synchronized audio with the picture rather than adding it afterward.

It is the fourth major version of the Kling line, following Kling 3.0 in February 2026. Single-pass length runs 3 to 30 seconds against Kling 3.0's 3 to 15, output goes to 4K with 10-bit HDR, and it accepts up to 10 keyframe images.

A faster tier, Kling 4.0 Flash, has been in limited early access since September 28, 2026 at 720p and up to 20 seconds. You can run Kling 4.0 in the Kling AI video generator on this page or through the official Kling AI app.

Kling 4.0 is billed per second of output rather than per generation, so a failed render costs the same as a good one and a 5-second test costs a sixth of a 30-second take.

Three things move the rate: resolution is by far the largest factor, native audio adds to it, and the Flash tier is cheaper than full Kling 4.0 by design. Because cost scales with length rather than attempts, the cheapest way to work is to settle composition at a low resolution and render once at full quality.

Current per-second rates for every model and the credit pack prices are on the pricing page.

Yes, within limits. You get starter credits on this page with no card required, which covers a few short clips at 720p. That is enough to judge output quality on your own prompts before paying.

Free Kling 4.0 access does not include the longest durations or the highest resolution, since those consume more credits per second.

If you need unlimited Kling 4.0 generation, that requires a paid plan — no provider offers genuinely unlimited access to a model this expensive to run, and any site claiming otherwise is either rate-limiting you silently or running an older model.

Kling 4.0 Flash is the fast tier of the Kling 4.0 lineup, built for frequent creation rather than hero shots.

It generates 3 to 20 seconds at 720p, with Omni Reference still available. It opened to a limited group of users on September 28, 2026 — ahead of Kling 4.0 itself.

The trade against full Kling 4.0 is clear: you give up 4K, 10-bit HDR and the 30-second ceiling, and you get speed.

In practice that makes Flash the right place to settle composition, camera movement and keyframes before committing to a full-resolution render, and the sensible default for high-volume social output where 720p is the delivery format anyway.

Four things changed. Single-pass length doubles to 30 seconds from Kling 3.0's 15. Output adds 10-bit HDR at 1080p and 4K, which Kling 3.0 does not have. You get up to 10 keyframe images to pin exact story beats, plus 21:9 ultrawide framing and two-channel stereo audio.

Prompts run to 8,000 tokens. Reference handling moves to 15 items per generation — 10 images, 5 videos, 7 subjects — against Kling 3.0's narrower character-video system.

What has not changed is that Kling 3.0 is available now at published rates while Kling 4.0 is not yet on the API, so for short clips under about 10 seconds Kling 3.0 stays the sensible default.

Seedance 2.5 is ByteDance's competing model, released July 31, 2026, with 30 seconds per generation and 50 reference assets in one pass — 30 images, 10 video clips, 10 audio clips.

On single-pass length the two are level at 30 seconds. On references Seedance 2.5 is roughly 3x ahead of Kling 4.0's 15 items, which is the clearest reason to pick it.

Kling 4.0 leads on output: 4K with 10-bit HDR against Seedance 2.5's native 1080p, plus 21:9 framing and 10 keyframes with no published equivalent.

Pick Kling 4.0 if the deliverable is graded, wide, or has to hit specific story beats. Pick Seedance 2.5 if the job is reference-heavy compositing.

Kuaishou has confirmed that Kling 4.0 launches in October 2026. Kling 4.0 Flash, the faster tier in the same lineup, opened to a limited group of users for early access on September 28, 2026.

For context on the cadence: Kling 1.0 entered beta on June 10, 2024, Kling 2.0 arrived in April 2025, Kling 2.5 Turbo in September 2025, and Kling 3.0 on February 7, 2026, with Kling 3.0 Turbo and Omni following on June 17, 2026. Major versions have landed roughly ten months apart, which puts Kling 4.0 right on schedule.

Two capabilities are dated later than the model itself: 10-bit HDR output and multi-pass extension to 2 minutes are both listed as coming soon.

Output from paid plans is watermark-free and cleared for commercial use. Free-tier clips carry a watermark, which is the standard trade for generating without a card. Check the licensing terms on your plan before using a clip in a paid campaign — commercial rights come with the paid tiers, not the free one.

If you need a clean clip to show a client, the cheapest paid tier removes the watermark on every render from that point.

Up to 30 seconds in a single pass, with a flexible range starting at 3 seconds — double Kling 3.0's 15-second ceiling. Beyond that, video extension lets you extend a clip forward or backward across multiple passes up to 2 minutes total, which Kuaishou lists as coming soon rather than available at launch.

Kling 4.0 Flash, the fast tier, caps at 20 seconds. The practical difference 30 seconds makes is not length for its own sake: it is enough room for action, a scene change and an emotional beat to develop in sequence rather than one of them filling the whole clip.

Up to 10, placed anywhere on the timeline, plus first and last frame control. Each keyframe is an image the generation has to pass through, and the model fills the motion between them.

Across a 30-second take that is roughly one pinned moment every three seconds — enough to control camera movement, shot changes, character entrances and product reveals rather than describing them and hoping. Ten is also a practical ceiling: past about one keyframe every two seconds the segments get too short for an action to read.

Yes, and from several other inputs besides. Text-to-video and image-to-video are the two base modes. On top of those, Kling 4.0 accepts first and last frames, up to 10 keyframe images, and Omni Reference inputs covering up to 10 images, 5 video clips and 7 saved subjects plus voice samples.

A reference video can also drive a generation outright — upload a clip whose pacing and camera work you want, add your own assets, and the model builds new content on that structure. In practice most projects mix two or three of these rather than using one alone.

Yes, and this is one of the less-advertised capabilities. Kling 4.0 accepts up to 5 input video clips including one primary video, each 3 to 30 seconds, with the combined duration capped at 30 seconds.

Within that you can make targeted changes — a character's expression, body movement, camera position or camera movement, the overall style, or the background — while the rest of the scene stays put. Kuaishou also supports element removal and character or product replacement inside existing footage.

The practical value is that a client note about one detail no longer costs you a full regeneration: you change the moment, not the clip. For anything that needs a genuinely new scene rather than a modification, generation from a prompt is still the faster route.

Yes. Kling motion control lets you direct the camera the way you would on a real shoot — dolly, pan, tilt, rack focus, and macro moves — rather than hoping the model picks a good angle.

Kling 4.0 keeps the physics consistent while the camera moves — objects carry weight, collisions land where they should, and motion blur follows the actual movement.

Searches for Kling motion control rose sharply through 2026 across the 2.6 and 3.0 releases. It remains one of the features separating Kling from models where camera direction is guesswork.

Phrase the move as a single instruction per clause for the most reliable result. Reports add up to 10 keyframes per generation in Kling 4.0, which would let you pin an exact moment rather than describing it.

Yes. Kling 4.0 outputs 720p, 1080p and 4K, and adds 10-bit HDR at the top two resolutions — a capability Kling 3.0 does not have. Kling AI 4K output is generated at full resolution rather than upscaled afterward, so texture and grain hold up on a large screen where an upscaled clip goes soft.

HDR is the part worth waiting for: in backlit shots, night scenes and neon-lit settings it holds more detail in highlights and shadows and reduces colour banding, which gives you far more room when grading. Kuaishou lists 10-bit HDR as coming soon rather than available on day one.

Note that Kling 4.0 Flash, the early-access tier, is 720p and 8-bit SDR only.

About two minutes for a typical clip, though it varies with length, resolution, and whether audio is enabled. A short 720p draft comes back faster than a full-length 4K HDR render with native audio, and Kling 4.0 Flash is the cheaper tier for drafting at 720p.

The practical workflow is to draft short and cheap first: get the composition and camera move right at a low setting, then re-render at full length once you are happy.

Timestamp-level editing also means a single bad moment does not cost you a full regeneration — you fix that segment for a fraction of the credits a complete re-roll would take.