Model comparison
Claude Sonnet 4.5 Thinking vs Kimi K2
Head-to-head evidence from 1 shared benchmark result across 1 category. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Claude Sonnet 4.5 Thinking unranked (Not scored); Kimi K2 #189 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude Sonnet 4.5 Thinking and Kimi K2 share 1 comparable benchmark result. 0 of 8 categories are comparable. 1 result is unique to Claude Sonnet 4.5 Thinking; 13 to Kimi K2.
Updated July 23, 2026- Shared results
- 1
- Claude Sonnet 4.5 Thinking only
- 1
- Kimi K2 only
- 13
- Comparable categories
- 0 / 8
Benchmark data for Claude Sonnet 4.5 Thinking and Kimi K2 is coming soon on BenchLM.
Confidence note. This is a partial-evidence comparison with 1 shared benchmark result across 1 evidence category; 0 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
BenchLM has partial data for these models, but not enough overlapping benchmark coverage to produce a fair score-level comparison yet.
Claude Sonnet 4.5 Thinking has the larger context window at 200K, compared with 128K for Kimi K2.
Category breakdown
Exact category averages are shown below. Not measured means BenchLM does not have enough sourced public coverage for that model and category.
| Category | Claude Sonnet 4.5 Thinking | Δ | Kimi K2 |
|---|---|---|---|
| Math | Claude Sonnet 4.5 ThinkingNot measured | MarginNo overlap | Kimi K216.1 |
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Claude Sonnet 4.5 Thinking | Kimi K2 | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude Sonnet 4.5 ThinkingNot available | Kimi K2$0.6 input / $2.5 output | A complete price comparison is not available. |
| Generation speedtokens per second | Claude Sonnet 4.5 ThinkingNot available | Kimi K243 tok/s | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude Sonnet 4.5 ThinkingNot available | Kimi K21.51 s | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude Sonnet 4.5 Thinking200K | Kimi K2128K | Claude Sonnet 4.5 Thinking lists the larger context window. |
Benchmark Deep Dive
Agentic1 benchmarks
| Benchmark | Claude Sonnet 4.5 Thinking | Kimi K2 | Result |
|---|---|---|---|
| τ²-bench resultsSource | — | 61.1% | Not comparable |
Coding2 benchmarks
Reasoning2 benchmarks
Knowledge6 benchmarks
| Benchmark | Claude Sonnet 4.5 Thinking | Kimi K2 | Result |
|---|---|---|---|
| Artificial Analysis Intelligence IndexSource | — | 19.4% | Not comparable |
| AA-GPQA DiamondSource | — | 76.6% | Not comparable |
| AA-HLESource | — | 7.0% | Not comparable |
| AA-Omniscience IndexSource | — | -27.5% | Not comparable |
| AA-Omniscience AccuracySource | — | 26.8% | Not comparable |
| AA-Omniscience Hallucination RateSource | — | 74.2% | Not comparable |
Math2 benchmarks
Multimodal1 benchmarks
| Benchmark | Claude Sonnet 4.5 Thinking | Kimi K2 | Result |
|---|---|---|---|
| Design Arena WebsiteSource | 1219 | 1080 | Claude Sonnet 4.5 Thinking leads |
Inst. Following1 benchmarks
| Benchmark | Claude Sonnet 4.5 Thinking | Kimi K2 | Result |
|---|---|---|---|
| AA-IFBenchSource | — | 41.5% | Not comparable |
Frequently Asked Questions (3)
Can I compare Claude Sonnet 4.5 Thinking and Kimi K2 on BenchLM yet?
Not fully yet. BenchLM is tracking both models, but the sourced benchmark breakdown for this comparison is still coming soon.
Why does this comparison show “coming soon”?
BenchLM only shows category winners and benchmark-level calls when we have sourced results that can be compared fairly. For these models, the public benchmark coverage is not complete enough yet.
What data is available for Claude Sonnet 4.5 Thinking and Kimi K2 today?
Kimi K2: $0.60 input / $2.50 output per 1M tokens Both model pages still include creator, context window, reasoning mode, and other metadata while benchmark coverage fills in.
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