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Model comparison

Kimi K2.5 (Reasoning) vs o3-mini

Data verified

Head-to-head evidence from 7 shared benchmark results across 3 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.

59.35/100
Margin
11.9pts
← winning
OpenAI
47.41/100
2 category wins0 category wins

Public leaderboard positions: Kimi K2.5 (Reasoning) #57 (Estimated); o3-mini #136 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.

Evidence parity. Kimi K2.5 (Reasoning) and o3-mini share 7 comparable benchmark results. 2 of 8 categories are comparable. 20 results are unique to Kimi K2.5 (Reasoning); 3 to o3-mini.

Updated July 24, 2026
Shared results
7
Kimi K2.5 (Reasoning) only
20
o3-mini only
3
Comparable categories
2 / 8

Pick Kimi K2.5 (Reasoning) if you want the stronger benchmark profile. o3-mini only becomes the better choice if you need the larger 200K context window.

Confidence note. This is a partial-evidence comparison with 7 shared benchmark results across 3 evidence categories; 2 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.

Why this result

Kimi K2.5 (Reasoning) is clearly ahead on the BenchAlign aggregate, 59.35 to 47.41. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

Kimi K2.5 (Reasoning)'s sharpest advantage is in coding, where it averages 76.8 against 49.3. The single biggest benchmark swing on the page is SWE-bench Verified, 76.8% to 49.3%.

o3-mini is also the more expensive model on tokens at $1.10 input / $4.40 output per 1M tokens, versus $0.60 input / $3.00 output per 1M tokens for Kimi K2.5 (Reasoning). o3-mini gives you 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 scores and score margins for Kimi K2.5 (Reasoning) and o3-mini
CategoryKimi K2.5 (Reasoning)Δo3-mini
CodingKimi K2.5 (Reasoning)76.8Margin 27.5o3-mini49.3
KnowledgeKimi K2.5 (Reasoning)87.2Margin 10.0o3-mini77.2
AgenticKimi K2.5 (Reasoning)55.0MarginNo overlapo3-miniNot measured
MultimodalKimi K2.5 (Reasoning)78.5MarginNo overlapo3-miniNot measured
Inst. FollowingKimi K2.5 (Reasoning)Not measuredMarginNo overlapo3-mini93.9

Decisive benchmark drivers

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

More
A · Kimi K2.5 (Reasoning)B · o3-mini
  1. SWE-bench Verified

    Coding
    Source ↗
    A 76.8%B 49.3%
    Winner: Kimi K2.5 (Reasoning)Δ 27.5
    SWE-bench Verified: Kimi K2.5 (Reasoning) scored 76.8%; o3-mini scored 49.3%. Kimi K2.5 (Reasoning) wins this benchmark.
  2. GPQA

    Knowledge
    Source ↗
    A 87.6%B 77.2%
    Winner: Kimi K2.5 (Reasoning)Δ 10.4
    GPQA: Kimi K2.5 (Reasoning) scored 87.6%; o3-mini scored 77.2%. Kimi K2.5 (Reasoning) wins this benchmark.

Operational comparison

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

MetricKimi K2.5 (Reasoning)o3-miniComparison
Input / output priceUSD per 1M tokensKimi K2.5 (Reasoning)$0.6 input / $3 outputo3-mini$1.1 input / $4.4 outputKimi K2.5 (Reasoning) has the lower combined listed price.
Generation speedtokens per secondKimi K2.5 (Reasoning)Not availableo3-mini160 tok/sA complete speed comparison is not available.
First-answer latencyseconds to first tokenKimi K2.5 (Reasoning)Not availableo3-mini7.12 sA complete latency comparison is not available.
Context windowmaximum listed tokensKimi K2.5 (Reasoning)128Ko3-mini200Ko3-mini lists the larger context window.

Benchmark Deep Dive

Agentic
BenchmarkKimi K2.5 (Reasoning)o3-miniResult
Terminal-Bench 2.0Source 50.8%Not comparable
BrowseCompSource 60.6%Not comparable
APEX-Agents-AASource 11.5%Not comparable
τ²-bench resultsSource 95.9%28.7%Kimi K2.5 (Reasoning) leads
Gert LabsSource 32.58%Not comparable
AA Agentic IndexSource 21.7%Not comparable
GDPval-AASource 25.4%Not comparable
GDPval-AASource 1009Not comparable
CodingKimi K2.5 (Reasoning) wins
BenchmarkKimi K2.5 (Reasoning)o3-miniResult
SWE-bench VerifiedSource 76.8%49.3%Kimi K2.5 (Reasoning) leads
Vibe Code BenchSource 17.54%Not comparable
AA-SciCodeSource 49.0%39.9%Kimi K2.5 (Reasoning) leads
AA Coding IndexSource 46.8%Not comparable
Reasoning
BenchmarkKimi K2.5 (Reasoning)o3-miniResult
AA-LCRSource 65.3%Not comparable
CritPtSource 3.1%Not comparable
KnowledgeKimi K2.5 (Reasoning) wins
BenchmarkKimi K2.5 (Reasoning)o3-miniResult
GPQASource 87.6%77.2%Kimi K2.5 (Reasoning) leads
MMLU-ProSource 87.1%Not comparable
Artificial Analysis Intelligence IndexSource 35.4%19.0%Kimi K2.5 (Reasoning) leads
AA-GPQA DiamondSource 87.9%74.8%Kimi K2.5 (Reasoning) leads
AA-HLESource 29.4%8.7%Kimi K2.5 (Reasoning) leads
AA-Omniscience IndexSource -8.1%Not comparable
AA-Omniscience AccuracySource 34.3%Not comparable
AA-Omniscience Hallucination RateSource 64.6%Not comparable
MMLUSource 86.9%Not comparable
Math
BenchmarkKimi K2.5 (Reasoning)o3-miniResult
AIME 2025Source 96.1%Not comparable
AIME 2024Source 87.3%Not comparable
Multimodal
BenchmarkKimi K2.5 (Reasoning)o3-miniResult
MMMU-ProSource 78.5%Not comparable
AA-MMMU-ProSource 75.4%Not comparable
Design Arena WebsiteSource 1279Not comparable
Inst. Following
BenchmarkKimi K2.5 (Reasoning)o3-miniResult
AA-IFBenchSource 70.2%Not comparable
IFEvalSource 93.9%Not comparable
Frequently Asked Questions (3)

Which is better, Kimi K2.5 (Reasoning) or o3-mini?

Kimi K2.5 (Reasoning) is ahead on BenchLM's BenchAlign leaderboard, 59.35 to 47.41. The biggest single separator in this matchup is SWE-bench Verified, where the scores are 76.8% and 49.3%.

Which is better for knowledge tasks, Kimi K2.5 (Reasoning) or o3-mini?

Kimi K2.5 (Reasoning) has the edge for knowledge tasks in this comparison, averaging 87.2 versus 77.2. Inside this category, AA-HLE is the benchmark that creates the most daylight between them.

Which is better for coding, Kimi K2.5 (Reasoning) or o3-mini?

Kimi K2.5 (Reasoning) has the edge for coding in this comparison, averaging 76.8 versus 49.3. Inside this category, SWE-bench Verified is the benchmark that creates the most daylight between them.

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Last updated: July 24, 2026

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