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Model comparison

Claude Sonnet 4.6 vs Mistral Medium 3.5 128B

Data verified

Head-to-head evidence from 14 shared benchmark results across 6 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.

64.3/100
No comparison
0 category wins1 category wins

Public leaderboard positions: Claude Sonnet 4.6 #35 (Supported); Mistral Medium 3.5 128B unranked (Not scored). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.

Evidence parity. Claude Sonnet 4.6 and Mistral Medium 3.5 128B share 14 comparable benchmark results. 1 of 8 categories are comparable. 19 results are unique to Claude Sonnet 4.6; 11 to Mistral Medium 3.5 128B.

Updated July 27, 2026
Shared results
14
Claude Sonnet 4.6 only
19
Mistral Medium 3.5 128B only
11
Comparable categories
1 / 8

Treat this as a split decision. Claude Sonnet 4.6 makes more sense if you would rather avoid the extra latency and token burn of a reasoning model; Mistral Medium 3.5 128B is the better fit if coding is the priority or you want the cheaper token bill.

Confidence note. This is a partial-evidence comparison with 14 shared benchmark results across 6 evidence categories; 1 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 4.6 and Mistral Medium 3.5 128B finish on the same BenchAlign overall score, so this is less about a single winner and more about where the edge shows up. The BenchAlign headline says tie; the benchmark table is where the real choice happens.

Claude Sonnet 4.6 is also the more expensive model on tokens at $3.00 input / $15.00 output per 1M tokens, versus $1.50 input / $7.50 output per 1M tokens for Mistral Medium 3.5 128B. That is roughly 2.0x on output cost alone. Mistral Medium 3.5 128B is the reasoning model in the pair, while Claude Sonnet 4.6 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. Mistral Medium 3.5 128B gives you the larger context window at 256K, compared with 200K for Claude Sonnet 4.6.

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 scores and score margins for Claude Sonnet 4.6 and Mistral Medium 3.5 128B
CategoryClaude Sonnet 4.6ΔMistral Medium 3.5 128B
CodingClaude Sonnet 4.669.1Margin 8.5Mistral Medium 3.5 128B77.6
AgenticClaude Sonnet 4.665.2MarginNo overlapMistral Medium 3.5 128BNot measured
KnowledgeClaude Sonnet 4.666.0MarginNo overlapMistral Medium 3.5 128BNot measured
MathClaude Sonnet 4.626.4MarginNo overlapMistral Medium 3.5 128BNot measured
MultimodalClaude Sonnet 4.677.4MarginNo overlapMistral Medium 3.5 128BNot measured

Decisive benchmark drivers

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

More
A · Claude Sonnet 4.6B · Mistral Medium 3.5 128B
  1. SWE-bench Verified

    Coding
    Source ↗
    A 79.6%B 77.6%
    Winner: Claude Sonnet 4.6Δ 2
    SWE-bench Verified: Claude Sonnet 4.6 scored 79.6%; Mistral Medium 3.5 128B scored 77.6%. Claude Sonnet 4.6 wins this benchmark.

Operational comparison

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

MetricClaude Sonnet 4.6Mistral Medium 3.5 128BComparison
Input / output priceUSD per 1M tokensClaude Sonnet 4.6$3 input / $15 outputMistral Medium 3.5 128B$1.5 input / $7.5 outputMistral Medium 3.5 128B has the lower combined listed price.
Generation speedtokens per secondClaude Sonnet 4.644 tok/sMistral Medium 3.5 128BNot availableA complete speed comparison is not available.
First-answer latencyseconds to first tokenClaude Sonnet 4.61.48 sMistral Medium 3.5 128BNot availableA complete latency comparison is not available.
Context windowmaximum listed tokensClaude Sonnet 4.6200KMistral Medium 3.5 128B256KMistral Medium 3.5 128B lists the larger context window.

Benchmark Deep Dive

Agentic
BenchmarkClaude Sonnet 4.6Mistral Medium 3.5 128BResult
Terminal-Bench 2.0Source 59.1%Not comparable
OSWorld-VerifiedSource 72.1%Not comparable
Claw-EvalSource 67.8%Not comparable
CyberGymSource 65.2%Not comparable
τ²-bench resultsSource 79.5%94.2%Mistral Medium 3.5 128B leads
Gert LabsSource 62.92%39.10%Claude Sonnet 4.6 leads
OSWorld 2.0Source 8.3%Not comparable
JobBenchSource 36.9%Not comparable
τ³-bench resultsSource 91.4%Not comparable
AA Agentic IndexSource 19.0%Not comparable
GDPval-AASource 21.6%Not comparable
GDPval-AASource 933Not comparable
AA EnterpriseOps-GymSource 33.7%Not comparable
AA Harvey LABSource 69.1%Not comparable
terminalBenchHardSource 33.3%Not comparable
AA BriefcaseSource 516Not comparable
AA Tau3 BankingSource 14.4%Not comparable
CodingMistral Medium 3.5 128B wins
BenchmarkClaude Sonnet 4.6Mistral Medium 3.5 128BResult
SWE-bench VerifiedSource 79.6%77.6%Claude Sonnet 4.6 leads
SWE-RebenchSource 60.7%Not comparable
React Native EvalsSource 80.6%Not comparable
Vibe Code BenchSource 51.48%Not comparable
cursorBench31Source 48.8%Not comparable
AA-SciCodeSource 46.9%39.6%Claude Sonnet 4.6 leads
FrontierCode 1.1 MainSource 24.3%Not comparable
AA Coding IndexSource 46.9%Not comparable
Reasoning
BenchmarkClaude Sonnet 4.6Mistral Medium 3.5 128BResult
AA-LCRSource 57.7%61.0%Mistral Medium 3.5 128B leads
CritPtSource 0.9%0.0%Claude Sonnet 4.6 leads
Knowledge
BenchmarkClaude Sonnet 4.6Mistral Medium 3.5 128BResult
GPQASource 89.9%Not comparable
SuperGPQASource 95%Not comparable
MMLU-ProSource 79.2%Not comparable
HLESource 49%Not comparable
Artificial Analysis Intelligence IndexSource 35.9%29.9%Claude Sonnet 4.6 leads
AA-GPQA DiamondSource 79.9%74.8%Claude Sonnet 4.6 leads
AA-HLESource 13.2%12.8%Claude Sonnet 4.6 leads
AA-Omniscience IndexSource -2.9%-36.3%Claude Sonnet 4.6 leads
AA-Omniscience AccuracySource 38.0%25.1%Claude Sonnet 4.6 leads
AA-Omniscience Hallucination RateSource 65.9%82.0%Claude Sonnet 4.6 leads
AA Openness IndexSource 33.3%Not comparable
Math
BenchmarkClaude Sonnet 4.6Mistral Medium 3.5 128BResult
FrontierMath v2 (Tiers 1-3)Source 32.400%Not comparable
FrontierMath v2 (Tier 4)Source 8.300%Not comparable
Multimodal
BenchmarkClaude Sonnet 4.6Mistral Medium 3.5 128BResult
CharXivSource 77.4%Not comparable
AA-MMMU-ProSource 70.6%64.9%Claude Sonnet 4.6 leads
Design Arena WebsiteSource 1310Not comparable
Inst. Following
BenchmarkClaude Sonnet 4.6Mistral Medium 3.5 128BResult
AA-IFBenchSource 41.2%68.8%Mistral Medium 3.5 128B leads
Frequently Asked Questions (2)

Which is better, Claude Sonnet 4.6 or Mistral Medium 3.5 128B?

Claude Sonnet 4.6 and Mistral Medium 3.5 128B are tied on the BenchAlign overall score, so the right pick depends on which category matters most for your use case.

Which is better for coding, Claude Sonnet 4.6 or Mistral Medium 3.5 128B?

Mistral Medium 3.5 128B has the edge for coding in this comparison, averaging 77.6 versus 69.1. Inside this category, AA-SciCode is the benchmark that creates the most daylight between them.

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Last updated: July 27, 2026

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