When to choose Kling 4.0 and when Grok Imagine Video
Kling 4.0
Input photos: up to 8 vs up to 7 for Grok Imagine Video
Input videos: up to 5 vs No for Grok Imagine Video
Input audio files: up to 3 vs No for Grok Imagine Video
Prompt limit: 8,000 characters vs 5,000 characters for Grok Imagine Video
Grok Imagine Video
Price, 1 s · 1080p: ≈ 6.38 coins vs ≈ 18.22 coins · Reference for Kling 4.0
Extra modes: normal / fun / spicy vs No for Kling 4.0
Minimum duration: 1 s vs 3 s for Kling 4.0
Key differences
Kling 4.0: A clip of up to 30 seconds from text and references or from a chain of keyframes: named characters, voice samples and exact frames.
Grok Imagine Video: Animate a frame, try several ideas and build a clip lasting 6–30 seconds.
Specifications
Spec
Kling 4.0
Grok Imagine Video
Model variants
Reference / Keyframes
Grok Imagine Video
Generation modes
from text / from first and last frames / from references
from text / from first and last frames / from references
First frame
Yes
Yes
Last frame
Yes
Yes
Input photos
up to 8
up to 7
Input videos
up to 5
No
Input audio files
up to 3
No
Input video length
2–30 s
No
Extra modes
No
normal / fun / spicy
Minimum duration
3 s
1 s
Maximum duration
30 s
30 s
Resolutions
720p / 1080p
480p / 720p / 1080p
Aspect ratios
9:16 / 16:9 / 1:1 / auto / 21:9
9:16 / 16:9 / 1:1 / 2:3 / 3:2
Prompt limit
8,000 characters
5,000 characters
Price, 1 s · 1080p
≈ 18.22 coins · Reference
≈ 6.38 coins
What to compare visually
For a fair A/B test, use the same scene and, where both modes allow it, the same first frame. Inspect motion continuity, character and object consistency, physics and contacts, camera behavior, temporal deformation, in-clip cuts and audio synchronization.
What to inspect with Kling 4.0
A clip of up to 30 seconds from text and references or from a chain of keyframes: named characters, voice samples and exact frames.
Text and references: up to 10 reference photos and 5 videos, up to 7 characters (2–4 photos or one 3–8 second video clip each) and up to 3 voice samples. The Video sound switch applies only to reference videos.
Keyframes: a first frame, a last frame and up to 8 middle frames. The total number of frames depends on the duration and never exceeds 10.
The modes do not mix: Keyframes accepts no video, and characters and voices belong only to Text and references mode.
A hero photo must be at least 300 pixels on the short side; a video character needs at least 700 pixels and one continuous shot.
What to inspect with Grok Imagine Video
Animate a frame, try several ideas and build a clip lasting 6–30 seconds.
Text or photos, 6–30 seconds, at 480p, 720p or 1080p.
Up to 7 photos at 480p and 720p; one at 1080p. Presentation modes include Normal, Fun and Spicy.
Presentation modes do not override service restrictions or guarantee particular content.
Inspect identity, clothing and props throughout longer clips.
How to run a fair comparison
Fix the scene, the first frame (if both models accept one), the duration and the resolution.
Judge motion, not stills: faces, hands and objects should hold across the whole clip and at cuts.
If sound matters, listen to it separately: dialogue, effects and lip sync differ between models.
Price a finished clip, not a second: the per-second rate times your real duration, rounded up once.
Sources
Prices, availability and specifications come from the Mixer AI catalog. This is not an independent test: try both models on the same task before choosing.
Which is cheaper: Kling 4.0 or Grok Imagine Video?
Price, 1 s · 1080p: Kling 4.0 ≈ 18.22 coins · Reference, Grok Imagine Video ≈ 6.38 coins. Grok Imagine Video is cheaper. The total depends on your settings: the price of the chosen options is shown in the interface before you run.
How does Kling 4.0 differ from Grok Imagine Video?
Kling 4.0 — input photos: up to 8; input videos: up to 5; input audio files: up to 3. Grok Imagine Video — price, 1 s · 1080p: ≈ 6.38 coins; extra modes: normal / fun / spicy.
How should I compare Kling 4.0 and Grok Imagine Video fairly?
Fix the scene, first frame, duration and resolution. Watch the motion across the whole clip and listen to the sound separately. Price the finished clip, not one second.
Are both models available in Mixer AI?
Yes. Both models are in the Mixer AI video catalog; the launch button on the page opens Canvas on a computer and the Studio on a phone. The page exists only for models in the current catalog.
Which model is better?
There is no single winner. First rule out the model that lacks the duration, first or last frame, sound or resolution you need, then compare clips on your own scene. The table highlights only measurable differences.