Short answer: Kling 4.0 Flash is the faster, lighter model: 3–20 seconds at 720p in 8-bit SDR, without first-and-last frames or multi-keyframes. The full Kling 4.0 model makes 3–30 second clips, accepts up to 10 keyframes and up to 15 reference assets, and outputs 720p, 1080p and 4K. Both are available now: Flash opened first on September 28, 2026, and the full model launched globally on October 15, 2026.
Last verified: November 11, 2026
This page compares the two Kling 4.0 options by timeline, limits and use case. For Flash access and limits in more depth, read the Kling 4.0 Flash guide; for the full feature set, see Kling 4.0 features and Kling 4.0 modes.
When did Kling 4.0 Flash and the full model launch?
| Date (2026) | What changed | Source |
|---|---|---|
| September 28 | Kling 4.0 Flash opens in early access to a limited group of creators | Kling 4.0 Flash announcement |
| October 15 | Full Kling 4.0 launches globally | Kuaishou investor release, October 16 |
| October 28 | Kling 4.0 API fully available | Kling Video API pricing |
| November 4 | Kling 4.0 Flash API available | Kling Video API pricing |
| Now | Flash and the full model are both available; pick by length and controls | Kling 4.0 User Guide |
Flash opened first as a lighter subset of Kling 4.0. Now that both are available, compare them on who each is for and which controls you need. For the full launch timeline, see Kling 4.0 release date.
Flash vs full: comparison table
| Dimension | Kling 4.0 Flash | Full Kling 4.0 |
|---|---|---|
| Availability | Available now (opened September 28, 2026) | Available now (global launch October 15, 2026) |
| Length (single generation) | 3–20 seconds | 3–30 seconds |
| Resolution / color | 720p, 8-bit SDR | 720p, 1080p and 4K; 10-bit HDR marked coming soon |
| Aspect ratios | Not listed separately in the User Guide | 21:9, 16:9, 1:1, 9:16 and Auto |
| First-and-last frames | Not supported | Supported |
| Multi-keyframes | Not supported | Up to 10 keyframes |
| Omni Reference | Supported | Up to 15 reference assets |
For length planning, see Kling 4.0 video length. For resolution and HDR status, see Kling 4.0 4K.
Who should use Flash vs the full model?
Choose Flash-style workflows when:
- You need a fast draft of a text-to-video or image-to-video idea within 20 seconds at 720p.
- You do not need a fixed ending frame or a multi-keyframe timing plan.
- You want quicker, lower-cost iterations before a final render.
Choose the full model when:
- You need up to 30 seconds in one generation.
- You need first-and-last frames or up to 10 keyframes.
- You are combining a larger Omni Reference set (up to 15 assets).
- You need 1080p or 4K delivery.
Neither column is a promise that every clip will match a storyboard on the first try. Review motion, identity, and audio after each generation. For first-run habits, follow how to use Kling 4.0.
What is still coming soon for Kling 4.0?
Kling 4.0 outputs 720p, 1080p and 4K, and 21:9 is available now. 10-bit HDR and Video Extension (up to two minutes) are still marked as coming soon in Kling's User Guide, with no published release date.
Check the Kling 4.0 User Guide for the latest status before you promise a client HDR delivery.
How can you test both on Kling4.tv?
New accounts on Kling4.tv receive 40 credits, enough to generate one video. Use that first video to test one clear question, such as whether your shot needs a fixed last frame, before you plan a longer keyframe shot. The generator shows the credits for your settings before you submit.
FAQ
What is the difference between Kling 4.0 Flash and the full model?
Flash is the lighter option: 3–20 seconds at 720p in 8-bit SDR, without first-and-last frames or multi-keyframes. The full model makes 3–30 second clips at up to 4K and adds keyframe and wider reference control. See the comparison table above.
Is Kling 4.0 Flash still available after the full launch?
Yes. Flash opened in early access on September 28, 2026 and is now offered alongside the full model. Check the model label in the menu before you submit.
Does Flash support first-and-last frames or multi-keyframes?
No. Kling's User Guide lists first and last frames and multi-keyframes for the full model only.
Does the full Kling 4.0 model support 4K and HDR?
It outputs 720p, 1080p and 4K now. 10-bit HDR is still marked as coming soon in Kling's User Guide, with no published date.
How should I pick a model for my first test?
If you only need a short 720p draft without keyframe control, Flash-style limits may be enough. If you need ~30 seconds, ending-frame control, or more keyframes, plan on the full model. Start from how to use Kling AI.
Sources
- Kling 4.0 User Guide, Kling AI
- Kling 4.0 feature page, Kling AI
- Kuaishou investor release on the October 15, 2026 global launch (dated October 16, 2026)
- Kling Video API pricing, Kling AI