Model comparison
Claude Opus 4.8 vs Kimi K2.6
Head-to-head evidence from 37 shared benchmark results across 7 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Claude Opus 4.8 #5 (Supported); Kimi K2.6 #74 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude Opus 4.8 and Kimi K2.6 share 37 comparable benchmark results. 5 of 8 categories are comparable. 16 results are unique to Claude Opus 4.8; 14 to Kimi K2.6.
Updated July 23, 2026- Shared results
- 37
- Claude Opus 4.8 only
- 16
- Kimi K2.6 only
- 14
- Comparable categories
- 5 / 8
Pick Claude Opus 4.8 if you want the stronger benchmark profile. Kimi K2.6 only becomes the better choice if mathematics is the priority or you want the cheaper token bill.
Confidence note. This is a partial-evidence comparison with 37 shared benchmark results across 7 evidence categories; 5 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
Claude Opus 4.8 is clearly ahead on the BenchAlign aggregate, 78.34 to 56.79. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
Claude Opus 4.8's sharpest advantage is in knowledge, where it averages 62.7 against 42.2. The single biggest benchmark swing on the page is HLE, 57.9% to 34.7%. Kimi K2.6 does hit back in mathematics, so the answer changes if that is the part of the workload you care about most.
Claude Opus 4.8 is also the more expensive model on tokens at $5.00 input / $25.00 output per 1M tokens, versus $0.95 input / $4.00 output per 1M tokens for Kimi K2.6. That is roughly 6.3x on output cost alone. Claude Opus 4.8 gives you the larger context window at 1M, compared with 256K for Kimi K2.6.
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 4.8 | Δ | Kimi K2.6 |
|---|---|---|---|
| Knowledge | Claude Opus 4.862.7 | Margin← 20.5 | Kimi K2.642.2 |
| Coding | Claude Opus 4.881.1 | Margin← 16.7 | Kimi K2.664.4 |
| Math | Claude Opus 4.853.9 | Margin→ 13.2 | Kimi K2.667.1 |
| Agentic | Claude Opus 4.880.3 | Margin← 6.8 | Kimi K2.673.5 |
| Multimodal | Claude Opus 4.877.0 | Margin→ 2.8 | Kimi K2.679.8 |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
HLE
KnowledgeA 57.9%B 34.7%Winner: Claude Opus 4.8Δ 23.2HLE: Claude Opus 4.8 scored 57.9%; Kimi K2.6 scored 34.7%. Claude Opus 4.8 wins this benchmark. - Source ↗
FrontierMath v2 (Tier 4)
MathA 31.250%B 14.580%Winner: Claude Opus 4.8Δ 16.7FrontierMath v2 (Tier 4): Claude Opus 4.8 scored 31.250%; Kimi K2.6 scored 14.580%. Claude Opus 4.8 wins this benchmark. - Source ↗
SWE-bench Pro
CodingA 69.2%B 58.6%Winner: Claude Opus 4.8Δ 10.6SWE-bench Pro: Claude Opus 4.8 scored 69.2%; Kimi K2.6 scored 58.6%. Claude Opus 4.8 wins this benchmark. - Source ↗
OSWorld-Verified
AgenticA 83.4%B 73.1%Winner: Claude Opus 4.8Δ 10.3OSWorld-Verified: Claude Opus 4.8 scored 83.4%; Kimi K2.6 scored 73.1%. Claude Opus 4.8 wins this benchmark. - Source ↗
CharXiv
MultimodalA 89.9%B 80.4%Winner: Claude Opus 4.8Δ 9.5CharXiv: Claude Opus 4.8 scored 89.9%; Kimi K2.6 scored 80.4%. Claude Opus 4.8 wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Claude Opus 4.8 | Kimi K2.6 | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude Opus 4.8$5 input / $25 output | Kimi K2.6$0.95 input / $4 output | Kimi K2.6 has the lower combined listed price. |
| Generation speedtokens per second | Claude Opus 4.8Not available | Kimi K2.6Not available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude Opus 4.8Not available | Kimi K2.6Not available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude Opus 4.81M | Kimi K2.6256K | Claude Opus 4.8 lists the larger context window. |
Benchmark Deep Dive
AgenticClaude Opus 4.8 wins24 benchmarks
| Benchmark | Claude Opus 4.8 | Kimi K2.6 | Result |
|---|---|---|---|
| Terminal-Bench 2.0Source | 74.6% | 66.7% | Claude Opus 4.8 leads |
| BrowseCompSource | 84.3% | 83.2% | Claude Opus 4.8 leads |
| DeepSearchQASource | 93.1% | 92.5% | Claude Opus 4.8 leads |
| OSWorld-VerifiedSource | 83.4% | 73.1% | Claude Opus 4.8 leads |
| Finance Agent v2Source | 53.9% | — | Not comparable |
| GDPval-AASource | 1594 | 1189 | Claude Opus 4.8 leads |
| MCP AtlasSource | 82.2% | 55.9% | Claude Opus 4.8 leads |
| ToolathlonSource | 59.9% | 50% | Claude Opus 4.8 leads |
| Gert LabsSource | 72.97% | 56.82% | Claude Opus 4.8 leads |
| AA Agentic IndexSource | 47.2% | 30.3% | Claude Opus 4.8 leads |
| τ²-bench resultsSource | 94.4% | 95.9% | Kimi K2.6 leads |
| GDPval-AASource | 54.7% | 34.5% | Claude Opus 4.8 leads |
| ResearchClawBenchSource | 21.1% | 18.0% | Claude Opus 4.8 leads |
| OSWorld 2.0Source | 20.6% | 4.6% | Claude Opus 4.8 leads |
| AA BriefcaseSource | 1347 | — | Not comparable |
| AA AutomationBenchSource | 48.5% | — | Not comparable |
| AA EnterpriseOps-GymSource | 44.0% | — | Not comparable |
| AA Harvey LABSource | 91.1% | — | Not comparable |
| AA Tau3 BankingSource | 27.6% | — | Not comparable |
| terminalBenchHardSource | 58.3% | 43.9% | Claude Opus 4.8 leads |
| aaTerminalBench21Source | 84.6% | — | Not comparable |
| Claw-EvalSource | — | 62.3% | Not comparable |
| WideResearchSource | — | 80.8% | Not comparable |
| APEX-Agents-AASource | — | 28.5% | Not comparable |
CodingClaude Opus 4.8 wins13 benchmarks
| Benchmark | Claude Opus 4.8 | Kimi K2.6 | Result |
|---|---|---|---|
| SWE-bench VerifiedSource | 88.6% | 80.2% | Claude Opus 4.8 leads |
| SWE-bench ProSource | 69.2% | 58.6% | Claude Opus 4.8 leads |
| SWE MultilingualSource | 84.4% | 76.7% | Claude Opus 4.8 leads |
| SWE MultimodalSource | 38.4% | — | Not comparable |
| Terminal-Bench 2.0Source | 74.6% | 66.7% | Claude Opus 4.8 leads |
| cursorBench31Source | 58.4% | 47.6% | Claude Opus 4.8 leads |
| cursorBench32Source | 62.3% | — | Not comparable |
| AA Coding IndexSource | 74.3% | 61.8% | Claude Opus 4.8 leads |
| AA-SciCodeSource | 53.5% | 53.5% | Tie |
| FrontierCode 1.1 MainSource | 46.5% | — | Not comparable |
| LiveCodeBench v6Source | — | 89.6% | Not comparable |
| SciCodeSource | — | 52.2% | Not comparable |
| Vibe Code BenchSource | — | 37.89% | Not comparable |
Reasoning2 benchmarks
KnowledgeClaude Opus 4.8 wins10 benchmarks
| Benchmark | Claude Opus 4.8 | Kimi K2.6 | Result |
|---|---|---|---|
| GPQASource | 93.6% | 90.5% | Claude Opus 4.8 leads |
| GPQA-DSource | 93.6% | 90.5% | Claude Opus 4.8 leads |
| HLESource | 57.9% | 34.7% | Claude Opus 4.8 leads |
| HLE w/o toolsSource | 49.8% | — | Not comparable |
| Artificial Analysis Intelligence IndexSource | 55.7% | 44.2% | Claude Opus 4.8 leads |
| AA-GPQA DiamondSource | 92.0% | 91.1% | Claude Opus 4.8 leads |
| AA-HLESource | 45.7% | 35.9% | Claude Opus 4.8 leads |
| AA-Omniscience IndexSource | 27.4% | 6.4% | Claude Opus 4.8 leads |
| AA-Omniscience AccuracySource | 46.6% | 32.8% | Claude Opus 4.8 leads |
| AA-Omniscience Hallucination RateSource | 35.9% | 39.3% | Claude Opus 4.8 leads |
MathKimi K2.6 wins6 benchmarks
| Benchmark | Claude Opus 4.8 | Kimi K2.6 | Result |
|---|---|---|---|
| USAMO 2026Source | 96.7% | — | Not comparable |
| FrontierMath v2 (Tiers 1-3)Source | 47.241% | 38.966% | Claude Opus 4.8 leads |
| FrontierMath v2 (Tier 4)Source | 31.250% | 14.580% | Claude Opus 4.8 leads |
| AIME26Source | — | 96.4% | Not comparable |
| HMMT Feb 2026Source | — | 92.7% | Not comparable |
| MMAnswerBenchSource | — | 86.0% | Not comparable |
Multilingual1 benchmarks
| Benchmark | Claude Opus 4.8 | Kimi K2.6 | Result |
|---|---|---|---|
| INCLUDESource | 87.6% | — | Not comparable |
MultimodalKimi K2.6 wins10 benchmarks
| Benchmark | Claude Opus 4.8 | Kimi K2.6 | Result |
|---|---|---|---|
| OfficeQA ProSource | 66.2% | — | Not comparable |
| ScreenSpot ProSource | 87.9% | — | Not comparable |
| CharXivSource | 89.9% | 80.4% | Claude Opus 4.8 leads |
| CharXiv w/o toolsSource | 80.5% | — | Not comparable |
| Design Arena WebsiteSource | 1270 | 1306 | Kimi K2.6 leads |
| MMMU-ProSource | — | 79.4% | Not comparable |
| MMMU-Pro w/ PythonSource | — | 80.1% | Not comparable |
| MathVisionSource | — | 87.4% | Not comparable |
| V*Source | — | 96.9% | Not comparable |
| AA-MMMU-ProSource | — | 79.4% | Not comparable |
Inst. Following1 benchmarks
| Benchmark | Claude Opus 4.8 | Kimi K2.6 | Result |
|---|---|---|---|
| AA-IFBenchSource | 62.2% | 76.0% | Kimi K2.6 leads |
Frequently Asked Questions (6)
Which is better, Claude Opus 4.8 or Kimi K2.6?
Claude Opus 4.8 is ahead on BenchLM's BenchAlign leaderboard, 78.34 to 56.79. The biggest single separator in this matchup is HLE, where the scores are 57.9% and 34.7%.
Which is better for knowledge tasks, Claude Opus 4.8 or Kimi K2.6?
Claude Opus 4.8 has the edge for knowledge tasks in this comparison, averaging 62.7 versus 42.2. Inside this category, HLE is the benchmark that creates the most daylight between them.
Which is better for coding, Claude Opus 4.8 or Kimi K2.6?
Claude Opus 4.8 has the edge for coding in this comparison, averaging 81.1 versus 64.4. Inside this category, AA Coding Index is the benchmark that creates the most daylight between them.
Which is better for math, Claude Opus 4.8 or Kimi K2.6?
Kimi K2.6 has the edge for math in this comparison, averaging 67.1 versus 53.9. Inside this category, FrontierMath v2 (Tier 4) is the benchmark that creates the most daylight between them.
Which is better for agentic tasks, Claude Opus 4.8 or Kimi K2.6?
Claude Opus 4.8 has the edge for agentic tasks in this comparison, averaging 80.3 versus 73.5. Inside this category, GDPval-AA is the benchmark that creates the most daylight between them.
Which is better for multimodal and grounded tasks, Claude Opus 4.8 or Kimi K2.6?
Kimi K2.6 has the edge for multimodal and grounded tasks in this comparison, averaging 79.8 versus 77. Inside this category, Design Arena Website is the benchmark that creates the most daylight between them.
Self-host vs API cost
Estimates at 50,000 req/day · 1000 tokens/req average.
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