Skip to main content

Model comparison

Claude Sonnet 5 vs Kimi K2.5

Data verified

Head-to-head evidence from 21 shared benchmark results across 5 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.

65.32/100
Margin
5.7pts
← winning
Moonshot AI
59.66/100
4 category wins0 category wins

Public leaderboard positions: Claude Sonnet 5 #29 (Estimated); Kimi K2.5 #54 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.

Evidence parity. Claude Sonnet 5 and Kimi K2.5 share 21 comparable benchmark results. 4 of 8 categories are comparable. 15 results are unique to Claude Sonnet 5; 42 to Kimi K2.5.

Updated July 23, 2026
Shared results
21
Claude Sonnet 5 only
15
Kimi K2.5 only
42
Comparable categories
4 / 8

Pick Claude Sonnet 5 if you want the stronger benchmark profile. Kimi K2.5 only becomes the better choice if you want the cheaper token bill or you would rather avoid the extra latency and token burn of a reasoning model.

Confidence note. This is a partial-evidence comparison with 21 shared benchmark results across 5 evidence categories; 4 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.

Why this result

Claude Sonnet 5 is clearly ahead on the BenchAlign aggregate, 65.32 to 59.66. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

Claude Sonnet 5's sharpest advantage is in agentic, where it averages 81.9 against 55. The single biggest benchmark swing on the page is Terminal-Bench 2.0, 80.4% to 50.8%.

Claude Sonnet 5 is also the more expensive model on tokens at $2.00 input / $10.00 output per 1M tokens, versus $0.60 input / $3.00 output per 1M tokens for Kimi K2.5. That is roughly 3.3x on output cost alone. Claude Sonnet 5 is the reasoning model in the pair, while Kimi K2.5 is not. That usually helps on harder chain-of-thought-heavy tests, but it can also mean more latency and more token spend in real use. Claude Sonnet 5 gives you the larger context window at 1M, compared with 256K for Kimi K2.5.

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 scores and score margins for Claude Sonnet 5 and Kimi K2.5
CategoryClaude Sonnet 5ΔKimi K2.5
AgenticClaude Sonnet 581.9Margin 26.9Kimi K2.555.0
CodingClaude Sonnet 576.7Margin 17.3Kimi K2.559.4
MultimodalClaude Sonnet 588.3Margin 9.8Kimi K2.578.5
KnowledgeClaude Sonnet 557.4Margin 0.5Kimi K2.556.9
ReasoningClaude Sonnet 5Not measuredMarginNo overlapKimi K2.561.0
MathClaude Sonnet 5Not measuredMarginNo overlapKimi K2.560.6
MultilingualClaude Sonnet 5Not measuredMarginNo overlapKimi K2.582.3
Inst. FollowingClaude Sonnet 5Not measuredMarginNo overlapKimi K2.593.9

Decisive benchmark drivers

The largest measured benchmark gaps in this matchup, with exact reported values.

More
A · Claude Sonnet 5B · Kimi K2.5
  1. Terminal-Bench 2.0

    Agentic
    Source ↗
    A 80.4%B 50.8%
    Winner: Claude Sonnet 5Δ 29.6
    Terminal-Bench 2.0: Claude Sonnet 5 scored 80.4%; Kimi K2.5 scored 50.8%. Claude Sonnet 5 wins this benchmark.
  2. HLE

    Knowledge
    Source ↗
    A 57.4%B 30.1%
    Winner: Claude Sonnet 5Δ 27.3
    HLE: Claude Sonnet 5 scored 57.4%; Kimi K2.5 scored 30.1%. Claude Sonnet 5 wins this benchmark.
  3. BrowseComp

    Agentic
    Source ↗
    A 84.7%B 60.6%
    Winner: Claude Sonnet 5Δ 24.1
    BrowseComp: Claude Sonnet 5 scored 84.7%; Kimi K2.5 scored 60.6%. Claude Sonnet 5 wins this benchmark.
  4. SWE-bench Pro

    Coding
    Source ↗
    A 63.2%B 50.7%
    Winner: Claude Sonnet 5Δ 12.5
    SWE-bench Pro: Claude Sonnet 5 scored 63.2%; Kimi K2.5 scored 50.7%. Claude Sonnet 5 wins this benchmark.
  5. SWE-bench Verified

    Coding
    Source ↗
    A 85.2%B 76.8%
    Winner: Claude Sonnet 5Δ 8.4
    SWE-bench Verified: Claude Sonnet 5 scored 85.2%; Kimi K2.5 scored 76.8%. Claude Sonnet 5 wins this benchmark.

Operational comparison

Runtime and commercial metrics are compared only when both models have a complete sourced value.

MetricClaude Sonnet 5Kimi K2.5Comparison
Input / output priceUSD per 1M tokensClaude Sonnet 5$2 input / $10 outputKimi K2.5$0.6 input / $3 outputKimi K2.5 has the lower combined listed price.
Generation speedtokens per secondClaude Sonnet 5Not availableKimi K2.545 tok/sA complete speed comparison is not available.
First-answer latencyseconds to first tokenClaude Sonnet 5Not availableKimi K2.52.38 sA complete latency comparison is not available.
Context windowmaximum listed tokensClaude Sonnet 51MKimi K2.5256KClaude Sonnet 5 lists the larger context window.

Benchmark Deep Dive

AgenticClaude Sonnet 5 wins
BenchmarkClaude Sonnet 5Kimi K2.5Result
Terminal-Bench 2.0Source 80.4%50.8%Claude Sonnet 5 leads
BrowseCompSource 84.7%60.6%Claude Sonnet 5 leads
HLE w/ toolsSource 57.4%Not comparable
OSWorld-VerifiedSource 81.2%Not comparable
GDPval-AASource 16071009Claude Sonnet 5 leads
AA Agentic IndexSource 46.7%21.7%Claude Sonnet 5 leads
GDPval-AASource 55.4%25.4%Claude Sonnet 5 leads
AA BriefcaseSource 1388Not comparable
AA AutomationBenchSource 39.2%Not comparable
AA EnterpriseOps-GymSource 44.7%Not comparable
AA Harvey LABSource 90.1%Not comparable
AA Tau3 BankingSource 28.2%Not comparable
aaTerminalBench21Source 80.5%Not comparable
Claw-EvalSource 52.3%Not comparable
QwenClawBenchSource 54.3%Not comparable
τ³-bench resultsSource 65.7%Not comparable
DeepSearchQASource 77.1%Not comparable
DeepPlanningSource 14.4%Not comparable
ToolathlonSource 27.8%Not comparable
MCP AtlasSource 29.5%Not comparable
MCP-TasksSource 59.1%Not comparable
WideResearchSource 72.7%Not comparable
τ²-bench resultsSource 95.9%Not comparable
APEX-Agents-AASource 11.5%Not comparable
Gert LabsSource 45.88%Not comparable
ResearchClawBenchSource 14.0%Not comparable
JobBenchSource 8.7%Not comparable
CodingClaude Sonnet 5 wins
BenchmarkClaude Sonnet 5Kimi K2.5Result
SWE-bench VerifiedSource 85.2%76.8%Claude Sonnet 5 leads
SWE-bench ProSource 63.2%50.7%Claude Sonnet 5 leads
SWE MultilingualSource 78.3%73%Claude Sonnet 5 leads
SWE MultimodalSource 28.1%Not comparable
Terminal-Bench 2.0Source 80.4%Not comparable
FrontierCode 1.1 MainSource 42.7%Not comparable
cursorBench32Source 61.5%Not comparable
AA Coding IndexSource 71.5%46.8%Claude Sonnet 5 leads
AA-SciCodeSource 53.6%49.0%Claude Sonnet 5 leads
SWE-bench Verified*Source 70.8%Not comparable
LiveCodeBench v6Source 85.0%Not comparable
SWE-RebenchSource 58.5%Not comparable
React Native EvalsSource 77.2%Not comparable
SciCodeSource 48.7%Not comparable
Reasoning
BenchmarkClaude Sonnet 5Kimi K2.5Result
AA-LCRSource 70.7%65.3%Claude Sonnet 5 leads
CritPtSource 16.9%3.1%Claude Sonnet 5 leads
LongBench v2Source 61%Not comparable
KnowledgeClaude Sonnet 5 wins
BenchmarkClaude Sonnet 5Kimi K2.5Result
HLESource 57.4%30.1%Claude Sonnet 5 leads
HLE w/o toolsSource 43.2%Not comparable
Artificial Analysis Intelligence IndexSource 53.4%35.4%Claude Sonnet 5 leads
AA-GPQA DiamondSource 91.1%87.9%Claude Sonnet 5 leads
AA-HLESource 39.6%29.4%Claude Sonnet 5 leads
AA-Omniscience IndexSource 15.3%-8.1%Claude Sonnet 5 leads
AA-Omniscience AccuracySource 38.3%34.3%Claude Sonnet 5 leads
AA-Omniscience Hallucination RateSource 37.3%64.6%Claude Sonnet 5 leads
GPQASource 87.6%Not comparable
GPQA-DSource 87.6%Not comparable
SuperGPQASource 69.2%Not comparable
MMLU-ProSource 87.1%Not comparable
MMLU-Pro (Arcee)Source 87.1%Not comparable
Math
BenchmarkClaude Sonnet 5Kimi K2.5Result
AIME 2025Source 96.1%Not comparable
AIME26Source 95.8%Not comparable
AIME25 (Arcee)Source 96.3%Not comparable
HMMT Feb 2025Source 95.4%Not comparable
HMMT Nov 2025Source 91.1%Not comparable
HMMT Feb 2026Source 87.1%Not comparable
MMAnswerBenchSource 81.8%Not comparable
FrontierMath v2 (Tiers 1-3)Source 27.900%Not comparable
FrontierMath v2 (Tier 4)Source 4.200%Not comparable
Multilingual
BenchmarkClaude Sonnet 5Kimi K2.5Result
MMLU-ProXSource 82.3%Not comparable
NOVA-63Source 56.0%Not comparable
MultimodalClaude Sonnet 5 wins
BenchmarkClaude Sonnet 5Kimi K2.5Result
CharXivSource 88.3%Not comparable
CharXiv w/o toolsSource 77%Not comparable
AA-MMMU-ProSource 77.3%75.4%Claude Sonnet 5 leads
Design Arena WebsiteSource 13141279Claude Sonnet 5 leads
MMMU-ProSource 78.5%Not comparable
Video-MMESource 87.4%Not comparable
MMVUSource 80.4%Not comparable
VideoMMMUSource 86.6%Not comparable
Inst. Following
BenchmarkClaude Sonnet 5Kimi K2.5Result
IFEvalSource 93.9%Not comparable
AA-IFBenchSource 70.2%Not comparable
Frequently Asked Questions (5)

Which is better, Claude Sonnet 5 or Kimi K2.5?

Claude Sonnet 5 is ahead on BenchLM's BenchAlign leaderboard, 65.32 to 59.66. The biggest single separator in this matchup is Terminal-Bench 2.0, where the scores are 80.4% and 50.8%.

Which is better for knowledge tasks, Claude Sonnet 5 or Kimi K2.5?

Claude Sonnet 5 has the edge for knowledge tasks in this comparison, averaging 57.4 versus 56.9. Inside this category, HLE is the benchmark that creates the most daylight between them.

Which is better for coding, Claude Sonnet 5 or Kimi K2.5?

Claude Sonnet 5 has the edge for coding in this comparison, averaging 76.7 versus 59.4. Inside this category, AA Coding Index is the benchmark that creates the most daylight between them.

Which is better for agentic tasks, Claude Sonnet 5 or Kimi K2.5?

Claude Sonnet 5 has the edge for agentic tasks in this comparison, averaging 81.9 versus 55. Inside this category, GDPval-AA is the benchmark that creates the most daylight between them.

Which is better for multimodal and grounded tasks, Claude Sonnet 5 or Kimi K2.5?

Claude Sonnet 5 has the edge for multimodal and grounded tasks in this comparison, averaging 88.3 versus 78.5. 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.

Claude Sonnet 5
API / mo$9,000
Self-host / moNot listed
Break-even
Proprietary model — self-hosting not applicable.
Kimi K2.5
API / mo$2,700
Self-host / mo$5,221
Break-even132M/day
Model the full break-even

Related Comparisons

Last updated: July 23, 2026

Choose a model with this week’s evidence

Join 2,000+ readers for ranking moves, pricing changes, and the claims that still need proof.

One email each week. Unsubscribe anytime.