Model comparison
Claude Opus 4.5 Thinking vs Kimi K2.5 (Reasoning)
Head-to-head evidence from 14 shared benchmark results across 6 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Claude Opus 4.5 Thinking #69 (Estimated); Kimi K2.5 (Reasoning) #57 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude Opus 4.5 Thinking and Kimi K2.5 (Reasoning) share 14 comparable benchmark results. 0 of 8 categories are comparable. 2 results are unique to Claude Opus 4.5 Thinking; 13 to Kimi K2.5 (Reasoning).
Updated July 23, 2026- Shared results
- 14
- Claude Opus 4.5 Thinking only
- 2
- Kimi K2.5 (Reasoning) only
- 13
- Comparable categories
- 0 / 8
Benchmark data for Claude Opus 4.5 Thinking and Kimi K2.5 (Reasoning) is coming soon on BenchLM.
Confidence note. This is a partial-evidence comparison with 14 shared benchmark results across 6 evidence categories; 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 Opus 4.5 Thinking has the larger context window at 200K, compared with 128K for Kimi K2.5 (Reasoning).
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 Opus 4.5 Thinking | Δ | Kimi K2.5 (Reasoning) |
|---|---|---|---|
| Agentic | Claude Opus 4.5 ThinkingNot measured | MarginNo overlap | Kimi K2.5 (Reasoning)55.0 |
| Coding | Claude Opus 4.5 ThinkingNot measured | MarginNo overlap | Kimi K2.5 (Reasoning)76.8 |
| Knowledge | Claude Opus 4.5 ThinkingNot measured | MarginNo overlap | Kimi K2.5 (Reasoning)87.2 |
| Multimodal | Claude Opus 4.5 ThinkingNot measured | MarginNo overlap | Kimi K2.5 (Reasoning)78.5 |
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Claude Opus 4.5 Thinking | Kimi K2.5 (Reasoning) | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude Opus 4.5 ThinkingNot available | Kimi K2.5 (Reasoning)$0.6 input / $3 output | A complete price comparison is not available. |
| Generation speedtokens per second | Claude Opus 4.5 ThinkingNot available | Kimi K2.5 (Reasoning)Not available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude Opus 4.5 ThinkingNot available | Kimi K2.5 (Reasoning)Not available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude Opus 4.5 Thinking200K | Kimi K2.5 (Reasoning)128K | Claude Opus 4.5 Thinking lists the larger context window. |
Benchmark Deep Dive
Agentic8 benchmarks
| Benchmark | Claude Opus 4.5 Thinking | Kimi K2.5 (Reasoning) | Result |
|---|---|---|---|
| τ²-bench resultsSource | 89.5% | 95.9% | Kimi K2.5 (Reasoning) leads |
| Terminal-Bench 2.0Source | — | 50.8% | Not comparable |
| BrowseCompSource | — | 60.6% | Not comparable |
| APEX-Agents-AASource | — | 11.5% | Not comparable |
| Gert LabsSource | — | 32.58% | Not comparable |
| AA Agentic IndexSource | — | 21.7% | Not comparable |
| GDPval-AASource | — | 25.4% | Not comparable |
| GDPval-AASource | — | 1009 | Not comparable |
Coding4 benchmarks
Reasoning2 benchmarks
Knowledge9 benchmarks
| Benchmark | Claude Opus 4.5 Thinking | Kimi K2.5 (Reasoning) | Result |
|---|---|---|---|
| Artificial Analysis Intelligence IndexSource | 40.8% | 35.4% | Claude Opus 4.5 Thinking leads |
| AA-GPQA DiamondSource | 86.6% | 87.9% | Kimi K2.5 (Reasoning) leads |
| AA-HLESource | 28.4% | 29.4% | Kimi K2.5 (Reasoning) leads |
| AA-Omniscience IndexSource | 13.3% | -8.1% | Claude Opus 4.5 Thinking leads |
| AA-Omniscience AccuracySource | 45.7% | 34.3% | Claude Opus 4.5 Thinking leads |
| AA-Omniscience Hallucination RateSource | 59.8% | 64.6% | Claude Opus 4.5 Thinking leads |
| AA MMLU-ProSource | 89.5% | — | Not comparable |
| GPQASource | — | 87.6% | Not comparable |
| MMLU-ProSource | — | 87.1% | Not comparable |
Math1 benchmarks
| Benchmark | Claude Opus 4.5 Thinking | Kimi K2.5 (Reasoning) | Result |
|---|---|---|---|
| AIME 2025Source | — | 96.1% | Not comparable |
Multilingual1 benchmarks
| Benchmark | Claude Opus 4.5 Thinking | Kimi K2.5 (Reasoning) | Result |
|---|---|---|---|
| AA Global-MMLU-LiteSource | 91.3% | — | Not comparable |
Multimodal3 benchmarks
Inst. Following1 benchmarks
| Benchmark | Claude Opus 4.5 Thinking | Kimi K2.5 (Reasoning) | Result |
|---|---|---|---|
| AA-IFBenchSource | 58.0% | 70.2% | Kimi K2.5 (Reasoning) leads |
Frequently Asked Questions (3)
Can I compare Claude Opus 4.5 Thinking and Kimi K2.5 (Reasoning) 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 Opus 4.5 Thinking and Kimi K2.5 (Reasoning) today?
Kimi K2.5 (Reasoning): $0.60 input / $3.00 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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