Kling 4 and Seedance 2.5 both generate up to 30 seconds of video with sound in a single pass, and each one leads in different jobs. Kling 4 gives you more control and costs less per 1080p second. Seedance 2.5 has the stronger independent quality scores and takes far more reference inputs.
Quick verdict:
- Choose Kling 4 for keyframe-directed shots, video-reference work and lower cost at 1080p.
- Choose Seedance 2.5 for the best blind-test quality scores today, very large reference sets and in-place region editing.
Both models are new, launched in July and October 2026. Every figure below comes from the vendors' own release notes and price lists or from named third-party tests, and is dated.
Kling 4 vs Seedance 2.5 at a glance
The two models match on clip length, so the differences that matter are control, references, resolution and price.
| Kling 4.0 | Seedance 2.5 | |
|---|---|---|
| Developer | Kuaishou | ByteDance |
| Released | October 15, 2026 (Flash early access September 28) | July 31, 2026 (previewed June 23) |
| Clip length per generation | 3–30 s | 4–30 s |
| Resolution available now | 720p, 1080p (4K listed; 10-bit HDR coming soon) | 480p, 720p, 1080p (no 4K) |
| Native audio | Two-channel stereo, lip sync | Generated in the same pass as the video |
| Keyframes | Up to 10 (start, middle, end) | Start and end frame |
| Reference inputs | Up to 15: 10 images, 5 videos (30 s total), 7 elements, voice | Up to 50: 30 images, 10 videos, 10 audio |
| Aspect ratios | 21:9, 16:9, 1:1, 9:16, Auto | Includes an adaptive setting |
| Editing | Re-edit using up to 5 clips | Region-level editing inside a shot |
| Official API, 1080p | $0.235/s (preview, API still closed) | $0.569/s (BytePlus) |
| Artificial Analysis text-to-video Elo | Unrated so far | 1,156–1,158 (#5) |
Sources: Kling release note via CellCog, TechPilot, Miracamp, Hedra, ArgoLink, Artificial Analysis.
Kling 4: what's new
Kling 4.0 doubles Kling's clip length and adds timeline-level control. Kuaishou opened Kling 4.0 Flash to a limited group on September 28, 2026, then made the full model available to every Kling account on October 15 (TechPilot).
What changed from Kling 3.0 (per Kling's release note):
- Clip length rises from 15 to 30 seconds per generation.
- Up to 10 keyframes, where Kling 3.0 took start and end frames.
- Up to 15 references per task, mixing images, video clips, elements and voice.
- Prompts up to 8,000 tokens and a new 21:9 aspect ratio.
- Two-channel stereo audio, and on-screen text in 9 languages including English, Chinese, Spanish and Hindi.
- Access through kling.ai, plus an MCP server and CLI so AI agents can drive it (CellCog).
Kling 4.0 Flash is the faster, lighter version: 3–20 second clips at 720p in 8-bit SDR, from text, a first frame or Omni Reference, with no keyframes.
Limits today:
- 10-bit HDR at 1080p and 4K, and extending a video to 2 minutes, are still marked coming soon.
- The API is announced and still closed to developers.
- No public leaderboard has rated Kling 4.0 yet (Moe Lueker).
Seedance 2.5: what's new
Seedance 2.5 doubles ByteDance's clip length and roughly quadruples its reference capacity. ByteDance previewed it at the Volcano Engine FORCE conference on June 23, 2026 and released it on July 31, first in its Jimeng and Dreamina apps, with API access through Volcano Engine and BytePlus ModelArk in early August (Miracamp).
What changed from Seedance 2.0:
- Clip length rises from 15 to 30 seconds in one continuous generation.
- Up to 50 references per generation: 30 images, 10 video clips and 10 audio files (The Decoder).
- Region-level editing swaps a subject, background or product inside a finished shot and keeps the rest of it.
- Audio is generated in the same pass as the picture, and dialogue in double quotes gets matching lip movement (Replicate).
- ByteDance claims about 20% better prompt adherence than 2.0 (TNW).
Limits today:
- No 4K. Some launch coverage reported native 4K, which belongs to a separate Seedance 2.0 upgrade. Seedance 2.5 launched at 720p, with 1080p on BytePlus from August 17 (Real AI Test).
- BytePlus ModelArk, the official API, is sold outside the US only. US developers use resellers such as Replicate, fal or Hedra (CellCog).
- One production team reports Seedance 2.5 rejects realistic face references, which complicates character consistency (CellCog).
Head-to-head: quality, control and cost
Quality benchmarks
Seedance 2.5 has independent scores, and Kling 4 has none yet. On Artificial Analysis's blind-vote leaderboards, Seedance 2.5 scores 1,156 Elo (#5) on text-to-video and 1,138 (#3) on image-to-video, both with audio (text-to-video, image-to-video). Kling's previous model, Kling 3.0 Pro, is the board's 1,000 anchor, roughly 150 points lower. As of October 21, 2026, no public arena had rated Kling 4.0 (Moe Lueker).
In one hands-on launch-day test, Seedance 2.0 looked more realistic than Kling 4.0 from text-only prompts, and Kling 4.0 was stronger with references: it held a face, helmet lettering and a reference video's camera path (Moe Lueker).
Control
Kling 4 offers finer timeline control, and Seedance 2.5 offers more grounding. Kling takes up to 10 keyframes, including middle frames, where Seedance takes start and end frames only. Seedance accepts up to 50 references against Kling's 15, which helps keep products, faces and brand style consistent across a long clip.
Cost
Kling 4 is cheaper per second at 1080p on both official and subscription pricing.
| Price point | Kling 4.0 | Seedance 2.5 |
|---|---|---|
| Official API, 720p, per second | $0.157 (preview) | $0.231 |
| Official API, 1080p, per second | $0.235 (preview) | $0.569 |
| 10 s clip at 1080p, official API | ~$2.35 | ~$5.69 |
| 10 s clip at 1080p with sound, Artlist | 2,750 credits (~$1.43) | 10,000 credits (~$5.21) |
API prices are for requests without video input. Kling 4.0 API rates are announced and still unpurchasable (TechPilot). Seedance rates are BytePlus list prices (ArgoLink), and resellers charge up to about twice as much (CellCog). Artlist figures are from the Moe Lueker test, checked October 21, 2026.
Kling's consumer plans start at $8.80 a month for 660 credits after a $6.99 first month (TechPilot).
Which should you choose?
Choose by what you start from and what you need to control.
| If you need… | Choose | Why |
|---|---|---|
| A shot that hits specific beats mid-clip | Kling 4 | Up to 10 keyframes, including middle frames |
| To copy a reference video's camera moves | Kling 4 | Up to 5 reference videos, tested to follow a real camera path |
| Lowest cost per 1080p second | Kling 4 | $0.235/s vs $0.569/s on official API pricing |
| Agent or automated pipelines today | Kling 4 | MCP server and CLI live now, API coming |
| Highest independently measured quality | Seedance 2.5 | #5 text-to-video, #3 image-to-video on Artificial Analysis |
| Many product, brand or style references at once | Seedance 2.5 | Up to 50 references vs 15 |
| Swapping one element in a finished shot | Seedance 2.5 | Region-level editing |
| An API you can buy today | Seedance 2.5 | Live on BytePlus and resellers since August |
| 4K or HDR masters | Neither yet | Kling lists HDR as coming soon, and Seedance 2.5 has no 4K |
Both go to 30 seconds, so the jobs above decide it.
In Planegraph, Prism makes video with Seedance 2.5 today, and Kling 4 is coming soon.
FAQ
Is Kling 4 better than Seedance 2.5?
It depends on the job. Seedance 2.5 ranks #5 on Artificial Analysis's text-to-video leaderboard, where Kling 4 has no score yet. Kling 4 offers more keyframe control and costs less per 1080p second.
How long can Kling 4 and Seedance 2.5 videos be?
Both generate up to 30 seconds in one pass. Kling 4.0's minimum is 3 seconds, and Seedance 2.5's is 4 seconds. Kling 4.0 Flash tops out at 20 seconds.
Do Kling 4 and Seedance 2.5 support 4K?
In practice, neither does yet. Kling lists 4K and marks 10-bit HDR at 1080p and 4K as coming soon, and launch-day tests found only 720p and 1080p. Seedance 2.5 tops out at 1080p.
How much does Seedance 2.5 cost?
On BytePlus ModelArk, ByteDance's official API, Seedance 2.5 costs about $0.103 per second at 480p, $0.231 at 720p and $0.569 at 1080p, for requests without video input.
How much does Kling 4 cost?
Kling plans start at $8.80 a month. Kling's announced API rates are $0.157 per second at 720p and $0.235 at 1080p, and the API is still closed.
Do both models generate audio?
Yes. Kling 4.0 outputs two-channel stereo with lip sync. Seedance 2.5 generates audio in the same pass as the video.
Can I use Seedance 2.5 in the US?
Yes, through third-party platforms such as Replicate, fal and Hedra. ByteDance's official BytePlus API is sold outside the US only.
Sources
- Kling 4.0 release note (Kling)
- Kling 4.0 Is Out: 30-Second Video, 15 References (CellCog)
- Kling 4.0: Pricing, API Cost & Flash (TechPilot)
- Kling 4.0 Review: I Tested It vs Seedance 2.0 and 2.5 (Moe Lueker)
- Seedance 2.5: ByteDance's AI Video Model Explained (Miracamp)
- ByteDance's Seedance 2.5 generates 30-second video clips (The Decoder)
- ByteDance unveils Seedance 2.5 (TNW)
- Seedance 2.5 on Replicate
- Seedance 2.5 on Hedra
- Seedance 2.5 API Pricing: 6 Providers Compared (ArgoLink)
- Seedance API Pricing: Token Rates, Tiers, and Per-Clip Costs (Real AI Test)
- Seedance 2.5 Pricing: Every API and Platform Compared (CellCog)
- Seedance 2.5 Face Likeness and Character Consistency (CellCog)
- Artificial Analysis Text-to-Video Leaderboard
- Artificial Analysis Image-to-Video Leaderboard