Mixer AI
Kling 4.0 vs Kling 4.0 Flash: specs and price
Kling 4.0 — resolutions: 720p / 1080p; maximum duration: 30 s.
When to choose Kling 4.0 and when Kling 4.0 Flash
Kling 4.0
- Resolutions: 720p / 1080p vs 720p for Kling 4.0 Flash
- Maximum duration: 30 s vs 20 s for Kling 4.0 Flash
- Generation modes: from text / from first and last frames / from references vs from text / from first frame / from references for Kling 4.0 Flash
- Last frame: Yes vs No for Kling 4.0 Flash
Kling 4.0 Flash
- The table shows no measurable edge for Kling 4.0 Flash: judge it by the result on your own scene.
Key differences
Specifications
| Spec | Kling 4.0 | Kling 4.0 Flash |
|---|---|---|
| Model variants | Reference / Keyframes | Flash |
| Generation modes | from text / from first and last frames / from references | from text / from first frame / from references |
| First frame | Yes | Yes |
| Last frame | Yes | No |
| Input photos | up to 8 | up to 7 |
| Input videos | up to 5 | up to 5 |
| Input audio files | up to 3 | No |
| Input video length | 2–30 s | No |
| Minimum duration | 3 s | 3 s |
| Maximum duration | 30 s | 20 s |
| Resolutions | 720p / 1080p | 720p |
| Aspect ratios | 9:16 / 16:9 / 1:1 / auto / 21:9 | 9:16 / 16:9 / 1:1 / auto / 21:9 |
| Prompt limit | 8,000 characters | 8,000 characters |
| Price, 1 s · 720p | — coins · Reference | — coins |
Price at the same settings
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 Kling 4.0 Flash
A lighter Kling 4.0: clips of 3–20 seconds in 720p from text and references, or from a start frame.
- Text and references: a prompt up to 8000 characters, up to 7 photos and up to 5 videos totaling up to 20 seconds; the Video sound switch keeps the sound of reference videos.
- Start frame: one optional photo; without it choose 16:9, 9:16, 1:1 or 21:9, with it the format follows the photo.
- Flash gives 720p and up to 20 seconds only; choose Kling 4.0 for 1080p and 30 seconds.
- Start frame mode accepts no video: videos belong to references mode only.
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.
What we compare
FAQ
Which is cheaper: Kling 4.0 or Kling 4.0 Flash?
Price, 1 s · 720p: the prices of Kling 4.0 and Kling 4.0 Flash are in the comparison table and always match the current tariff. 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 Kling 4.0 Flash?
Kling 4.0 — resolutions: 720p / 1080p; maximum duration: 30 s; last frame: Yes.
How should I compare Kling 4.0 and Kling 4.0 Flash 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.