Qwen3.6 Plus vs Kimi K2.5 vs Nemotron 3 Ultra 550B A55B
Too close to call on our weighted score (Qwen3.6 Plus 66, Kimi K2.5 65, Nemotron 3 Ultra 550B A55B 62). The right pick depends on what you value most.
Alibaba (Qwen)Qwen3.6 Plus
66/100- ECI147.6
- Price$0.50 / $3.00
- Context1M
Moonshot AIKimi K2.5
65/100- ECI148.0
- Price$0.60 / $3.00
- Context262K
NVIDIANemotron 3 Ultra 550B A55B
62/100- ECI146.2
- Price$0.50 / $2.50
- Context1M
Too close to call
It is close. Our weighted score puts them within a point (Qwen3.6 Plus 66/100, Kimi K2.5 65/100, Nemotron 3 Ultra 550B A55B 62/100), so choose by what matters most for your work: Kimi K2.5 for raw capability and Nemotron 3 Ultra 550B A55B on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.
- CapabilityKimi K2.5Capabilities Index (ECI): Kimi K2.5 148.0 · Qwen3.6 Plus 147.6 · Nemotron 3 Ultra 550B A55B 146.2
- Lowest priceNemotron 3 Ultra 550B A55BNemotron 3 Ultra 550B A55B $1.00 · Qwen3.6 Plus $1.13 · Kimi K2.5 $1.20 per 1M tokens (3:1 blend)
- Longest contextQwen3.6 Plus and Nemotron 3 Ultra 550B A55BQwen3.6 Plus 1,000,000 · Nemotron 3 Ultra 550B A55B 1,000,000 · Kimi K2.5 262,144 tokens
- Widest inputsQwen3.6 Plus and Kimi K2.5Qwen3.6 Plus: Text, Images, Video · Kimi K2.5: Text, Images, Video · Nemotron 3 Ultra 550B A55B: Text
- Self-hostingKimi K2.5 and Nemotron 3 Ultra 550B A55BPublishes downloadable weights
| Measure | Weight | Qwen3.6 Plus | Kimi K2.5 | Nemotron 3 Ultra 550B A55B |
|---|---|---|---|---|
| CapabilityCapabilities Index (ECI) | 50% | 75 | 76 | 73 |
| Price | 25% | 47 | 46 | 50 |
| Inputs & features | 15% | 70 | 80 | 45 |
| Context window | 10% | 60 | 37 | 60 |
| Overall | 100% | 66/100 | 65/100 | 62/100 |
Every spec in one table
Highlighted cells lead their row. Dashes mean the data is not published.
| Specification | Qwen3.6 PlusAlibaba (Qwen) | Kimi K2.5Moonshot AI | Nemotron 3 Ultra 550B A55BNVIDIA |
|---|---|---|---|
| Capability | |||
| Capabilities Index (ECI) | 147.6 | 148.0 (best) | 146.2 |
| ECI rank | #59 of 148 | #58 of 148 (best) | #70 of 148 |
| GPQA DiamondGraduate-level science questions | 88.4% (best) | 87.6% | 85.4% |
| FrontierMath Tiers 1–3Research-level mathematics | 38.3% | — | — |
| OTIS Mock AIME 2024–2025Competition mathematics | 93.3% (best) | 92.2% | 86.7% |
| SWE-bench VerifiedFixing real GitHub issues | 57.9% | 73.8% (best) | — |
| SimpleQA VerifiedShort factual questions | 44.1% (best) | 34.3% | — |
| Price per million tokens | |||
| Input | $0.50 (best) | $0.60 | $0.50 (best) |
| Output | $3.00 | $3.00 | $2.50 (best) |
| Cached input | $0.05 (best) | — | $0.15 |
| Blended (3:1) | $1.13 | $1.20 | $1.00 (best) |
| Long-context rate | Over 256K: $2.00 / $6.00 | Same rate | Same rate |
| Price source | Official Alibaba API | Median of 21 providers | Official Nvidia API |
| Limits | |||
| Context window | 1,000,000 tokens (best) | 262,144 tokens | 1,000,000 tokens (best) |
| Max output | 65,536 tokens | 262,144 tokens (best) | 128,000 tokens |
| Inputs and features | |||
| Text | Yes | Yes | Yes |
| Images | Yes | Yes | No |
| PDFs | No | No | No |
| Audio | No | No | No |
| Video | Yes | Yes | No |
| Reasoning | Yes | Yes | Yes |
| Tool calling | Yes | Yes | Yes |
| Structured output | No | Yes | Yes |
| Availability | |||
| Weights | Proprietary | Open | Open |
| API model ID | qwen3.6-plus | — | nvidia/nemotron-3-ultra-550b-a55b |
| API providers | 18 | 21 (best) | 21 (best) |
| Released | Apr 2, 2026 | Jan 27, 2026 | Jun 4, 2026 |
| Knowledge cutoff | Apr 2025 | Jan 2025 | — |
What would a month cost?
Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.
- Qwen3.6 Plus$11.00
- Kimi K2.5$12.00
- Nemotron 3 Ultra 550B A55B$10.00
Which should you choose?
Which is better: Qwen3.6 Plus, Kimi K2.5 or Nemotron 3 Ultra 550B A55B?
It is close. Our weighted score puts them within a point (Qwen3.6 Plus 66/100, Kimi K2.5 65/100, Nemotron 3 Ultra 550B A55B 62/100), so choose by what matters most for your work: Kimi K2.5 for raw capability and Nemotron 3 Ultra 550B A55B on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.
Which is cheaper, Qwen3.6 Plus, Kimi K2.5 or Nemotron 3 Ultra 550B A55B?
Nemotron 3 Ultra 550B A55B is cheaper at $0.50 input / $2.50 output per million tokens (official Nvidia API price). Qwen3.6 Plus costs $0.50 input / $3.00 output per million tokens (official Alibaba API price); Kimi K2.5 costs $0.60 input / $3.00 output per million tokens (median across 21 API providers). At a typical mix of three input tokens to one output token, that is $1.00 per million tokens for Nemotron 3 Ultra 550B A55B versus $1.13 for Qwen3.6 Plus (1.1× as much) and $1.20 for Kimi K2.5 (1.2× as much).
Which scores higher on benchmarks?
Kimi K2.5 scores higher on the Capabilities Index (ECI): Kimi K2.5 148.0 (#58 of 148), Qwen3.6 Plus 147.6 (#59 of 148) and Nemotron 3 Ultra 550B A55B 146.2 (#70 of 148). The confidence ranges of the top two overlap (146.5–149.3 vs 145.4–149.3), so treat the gap as small. On individual benchmarks: GPQA Diamond — Qwen3.6 Plus 88.4%, Kimi K2.5 87.6%, Nemotron 3 Ultra 550B A55B 85.4%; OTIS Mock AIME 2024–2025 — Qwen3.6 Plus 93.3%, Kimi K2.5 92.2%, Nemotron 3 Ultra 550B A55B 86.7%.
Which is better for coding?
There are no published SWE-bench Verified results for Nemotron 3 Ultra 550B A55B yet, so there is no like-for-like coding score. On overall capability, Kimi K2.5 leads, which tends to carry over to coding, but test on your own codebase. All three support tool calling for agent workflows.
Which has the bigger context window?
Qwen3.6 Plus and Nemotron 3 Ultra 550B A55B have the largest context windows (1,000,000 and 1,000,000 tokens), against 262,144 for Kimi K2.5. Maximum output per response: Qwen3.6 Plus up to 65,536, Kimi K2.5 up to 262,144, Nemotron 3 Ultra 550B A55B up to 128,000 tokens.
Which can read images, PDFs, audio or video?
Qwen3.6 Plus accepts text, images and video; Kimi K2.5 accepts text, images and video; Nemotron 3 Ultra 550B A55B accepts text. Qwen3.6 Plus handles the widest range of inputs.
Are any of these open source?
Kimi K2.5 and Nemotron 3 Ultra 550B A55B publishes its weights and can be self-hosted; Qwen3.6 Plus is proprietary.
Which is newer?
Nemotron 3 Ultra 550B A55B is the newest, released Jun 4, 2026. Qwen3.6 Plus came out Apr 2, 2026; Kimi K2.5 came out Jan 27, 2026. Knowledge cutoff: Qwen3.6 Plus Apr 2025, Kimi K2.5 Jan 2025.
How do you decide the winner?
Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Oct 4, 2026.
