AIREITERKling 4.0 is live, and an official API rollout has started. The catch is important: as of October 23, 2026, Kling still labels 4.0 Preview, while public documentation does not expose a verified 4.0 model ID, request schema, price, or general-availability guarantee.
Kling 4.0 availability by access route
Availability differs by access route. The web product and official MCP/CLI integrations are live; the API rollout has begun, but broad availability is not confirmed.
| Access route | Current status | Reference and keyframe position | Production judgment |
|---|---|---|---|
| Kling creator interface | Available | Model features are exposed through the first-party workflow | Suitable for supervised creative work |
| Kling MCP and CLI | Available | Officially includes Omni Reference and keyframe-to-video access | Suitable for agent-assisted workflows tied to a Kling account |
| Official Kling 4.0 API | Rolling out; developer page says Preview | Landing page advertises Omni Reference and multiple keyframes, but the public 4.0 payload is not documented | Prototype only after model access, limits, and billing are confirmed |
| Third-party hosted API | Provider-specific | Feature parity varies; a provider listing does not prove first-party API parity | Validate fields, outputs, and commercial terms before integration |
Kuaishou says Kling 4.0 officially launched on October 15, 2026, with native clips up to 30 seconds and integrations for Kling MCP and Kling CLI. The October 16 press release said enterprise and developer API access would arrive “soon.”
On October 21, the official @Kling_ai account announced, “KLING 4.0 API — Officially Rolling Out Now.” The wording confirms that an official API exists and deployment has begun; the post does not define eligibility, regions, pricing, quotas, or a GA date.
Does an official Kling 4.0 API exist?
Yes, but Kling has not confirmed unrestricted general availability. Developers should treat the October 21 announcement as the start of access expansion and verify the available model inside the Kling developer console.
Three first-party signals establish the status:
- Kuaishou's October 16 press release announced the October 15 model launch and described API access as forthcoming.
- Kling's official October 21 post said the API was “Officially Rolling Out Now.”
- The Kling Developer Platform presents Kling 4.0 with a Preview badge and advertises 30-second generation, Omni Reference, and multiple keyframes.
A public-GA declaration would normally identify a stable model name, endpoint-specific schema, pricing, quotas, regional availability, and service limits. Those 4.0-specific details were not verifiable in public documentation reviewed on October 23.
What the official API documentation proves
Kling's documentation proves that a functioning first-party API platform already exists. The official quick start documents API-key creation, Authorization: Bearer <API_KEY> authentication, resource packages, usage monitoring, and the base domain https://api-singapore.klingai.com.
Those platform instructions are not a Kling 4.0 request contract. The quick start does not provide a 4.0 model name, generation path, JSON body, response schema, 4.0 price, concurrency limit, or webhook behavior. Existing Kling API credentials therefore do not prove 4.0 access.
Why third-party availability is not official GA
A third-party host can make Kling 4.0 callable independently of broad first-party availability. The route also creates a separate contract for model identity, feature mapping, moderation, retention, billing, retries, and support.
An independent Kling 4.0 availability tracker claimed one priced WaveSpeedAI route through VideoRouter on October 17. The listing does not establish use of Kling's official API, support for all 15 references and 10 keyframes, or compatibility with a future GA contract. Require a paid test and an explicit feature schema instead of relying on the model label.
Reference images and keyframes: model support versus API support
Kling 4.0 supports reference images and multiple keyframes at the model level. Official materials confirm up to 15 combined reference assets and up to 10 keyframe images, but public materials do not document how each input is serialized in the official 4.0 API.
| Capability | Official model limit | Confirmed access surface | Public API detail still missing |
|---|---|---|---|
| Total reference assets | 15 per task | Creator workflow; model specification | 4.0 request object and weighting rules |
| Reference images | Up to 10 | Omni Reference | File types, byte limits, upload lifecycle |
| Reference videos | Up to 5, 30 seconds combined | Omni Reference | URL/upload format and per-file limits |
| Referenced subjects | Up to 7, including up to 3 video-derived elements | Omni Reference | Subject IDs and binding syntax |
| Voice reference | Supported as a reference type | Omni Reference | Audio format, consent controls, duration limit |
| Keyframe images | Up to 10 | Creator workflow; MCP/CLI keyframe-to-video | Timestamp syntax and interpolation controls |
| Editing source clips | Up to 5, 30 seconds combined | First-party model workflow | Editing endpoint and payload structure |
The limits come from the official Kling 4.0 model release, which states that the 15-item total cap spans images, videos, voice references, and elements. The category maxima are not additive: 10 images plus 5 videos consumes the complete allowance.
Kuaishou explicitly confirms that MCP and CLI can access “Omni Reference and keyframe-to-video generation.” Until a 4.0 endpoint reference appears, developers cannot assume that creator, MCP, and CLI controls map one-for-one to REST fields.
A user report shows why the access surface matters. Reddit user u/Feeling_Waltz_8180 asked about the redesigned interface:
“Did anyone also notice the ‘extract a frame’ from a previous output is gone?” Source: r/KlingAI_Videos
The observation is not an official product fact, but it captures the operational distinction: model-level frame support does not guarantee the same frame workflow on each surface.
Platform limits that matter before integration
Kling 4.0's confirmed model limits are broader than its confirmed API limits. Production designs should use documented values and treat announced output modes as unavailable until the selected route passes a test.
| Area | Kling 4.0 | Kling 4.0 Flash | Availability caveat |
|---|---|---|---|
| Generation modes | Text-to-video, image-to-video, first/last frame, multi-keyframe, Omni Reference | Text-to-video, image-to-video, Omni Reference | API parity is not publicly specified |
| Native duration | 3–30 seconds | 3–20 seconds | Access-surface limits may differ |
| Resolution | 720p and 1080p are the practical planning targets | 720p | Official materials list 4K for full 4.0 but also call 4K/HDR “coming soon” |
| Dynamic range | 10-bit HDR announced for 1080p/4K | 8-bit SDR | Do not promise HDR until the selected route exposes it |
| Audio | Two-channel stereo | Not fully detailed in the public table | API audio controls are not publicly mapped |
| Prompt length | Up to 8,000 tokens | Not specified | Endpoint-level validation rules are unpublished |
| Aspect ratios | 21:9, 16:9, 1:1, 9:16, Auto listed | Not fully detailed | Launch copy uses future tense for 21:9 in places |
Kling's specification table and release copy disagree on the launch status of 4K, HDR, and 21:9. Treat “listed” as untested until the selected access route exposes the option.
Video extension has the same caveat. The corporate launch announcement says repeated extension will support sequences up to two minutes, using future-tense wording. Native generation remains capped at 30 seconds.
Production decision: integrate now or wait
Teams should integrate Kling 4.0 now only when they can tolerate preview behavior and have verified the exact deployment route. Teams needing a stable public contract, predictable unit economics, or guaranteed feature parity should retain Kling 3.0 or another documented model and test 4.0 behind a feature flag.
| Use case | Recommendation | Reason |
|---|---|---|
| Creator using Kling's web interface | Use Kling 4.0 now | The first-party workflow exposes the model controls directly |
| Agent workflow with a Kling login | Test MCP/CLI now | Kuaishou confirms Omni Reference and keyframe-to-video integration |
| Internal prototype | Test official API if the console exposes the model | Preview limitations are manageable when failures are supervised |
| Customer-facing generation backend | Wait or retain a fallback | Public 4.0 schema, price, quotas, and GA commitments remain incomplete |
| Third-party API integration | Run a contract test first | Hosted access may omit references, keyframes, or other first-party controls |
Before accepting a route as production-ready:
- Confirm that the developer console exposes Kling 4.0 for the deployment account.
- Record the exact model ID, endpoint, and API version from first-party documentation or the provider's live schema.
- Submit one text-only, one image-reference, and one multi-keyframe request.
- Verify duration, resolution, audio, reference count, moderation, and failure billing.
- Measure queue time and completed-job cost instead of quoting a placeholder or an older Kling 3.0 rate.
- Keep the model ID configurable and preserve a documented fallback until Kling marks 4.0 generally available.
Kling 4.0 is available enough to prototype, but not documented enough for an assumption-driven production migration.
FAQ
Is the Kling 4.0 API publicly available?
The official Kling 4.0 API began rolling out on October 21, 2026, but Kling still labels the model Preview. Broad public availability has not been confirmed.
How do I get official Kling 4.0 API access?
Sign in to the Kling Developer Platform, create an API key, and check whether Kling 4.0 appears in the model or resource options. An existing API key does not guarantee 4.0 access.
Is Kling MCP the same as the Kling REST API?
No. MCP lets an AI agent invoke Kling tools through an account-connected integration, while the REST API uses HTTP endpoints and Bearer authentication. Kling 4.0 reached MCP/CLI before the official API rollout began.
Does the Kling 4.0 API support reference images and keyframes?
Kling 4.0 supports up to 10 reference images, 15 total references, and 10 keyframe images at the model level. The public 4.0 API reference has not documented the complete payload, so developers must verify those fields on the selected route.
Is third-party Kling 4.0 API access official?
A third-party endpoint is official only if the provider documents its upstream relationship or uses Kling-issued credentials. Treat a hosted endpoint as a separate service contract until the relationship and feature parity are verified.
What is official Kling 4.0 API pricing?
No public, 4.0-specific first-party API price was verifiable on October 23, 2026. Consumer credits, Kling 3.0 API rates, and third-party hosted prices are not official Kling 4.0 API pricing.