Skip to main content
BenchLM
Advertise

Model comparison

Claude Sonnet 4.6 vs DeepSeek V4 Flash

Data verified

Head-to-head evidence from 8 shared benchmark results across 4 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.

65.07/100
Margin
6.2pts
← winning
58.88/100
3 category wins1 category wins

Public leaderboard positions: Claude Sonnet 4.6 #32 (Supported); DeepSeek V4 Flash #61 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.

Evidence parity. Claude Sonnet 4.6 and DeepSeek V4 Flash share 8 comparable benchmark results. 4 of 8 categories are comparable. 25 results are unique to Claude Sonnet 4.6; 14 to DeepSeek V4 Flash.

Updated July 23, 2026
Shared results
8
Claude Sonnet 4.6 only
25
DeepSeek V4 Flash only
14
Comparable categories
4 / 8

Pick Claude Sonnet 4.6 if you want the stronger benchmark profile. DeepSeek V4 Flash 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 8 shared benchmark results across 4 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 4.6 is clearly ahead on the BenchAlign aggregate, 65.07 to 58.88. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

Claude Sonnet 4.6's sharpest advantage is in knowledge, where it averages 66 against 38.8. The single biggest benchmark swing on the page is HLE, 49% to 8.1%. DeepSeek V4 Flash does hit back in mathematics, so the answer changes if that is the part of the workload you care about most.

Claude Sonnet 4.6 is also the more expensive model on tokens at $3.00 input / $15.00 output per 1M tokens, versus $0.14 input / $0.28 output per 1M tokens for DeepSeek V4 Flash. That is roughly 53.6x on output cost alone. DeepSeek V4 Flash gives you the larger context window at 1M, 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 DeepSeek V4 Flash
CategoryClaude Sonnet 4.6ΔDeepSeek V4 Flash
KnowledgeClaude Sonnet 4.666.0Margin← 27.2DeepSeek V4 Flash38.8
AgenticClaude Sonnet 4.665.2Margin← 16.1DeepSeek V4 Flash49.1
MathClaude Sonnet 4.626.4Margin→ 14.4DeepSeek V4 Flash40.8
CodingClaude Sonnet 4.669.1Margin← 4.9DeepSeek V4 Flash64.2
MultimodalClaude Sonnet 4.677.4MarginNo overlapDeepSeek V4 FlashNot measured

Decisive benchmark drivers

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

More
A · Claude Sonnet 4.6B · DeepSeek V4 Flash

  1. HLE

    Knowledge
    Source ↗
    A 49%B 8.1%
    Winner: Claude Sonnet 4.6Δ 40.9
    HLE: Claude Sonnet 4.6 scored 49%; DeepSeek V4 Flash scored 8.1%. Claude Sonnet 4.6 wins this benchmark.

  2. GPQA

    Knowledge
    Source ↗
    A 89.9%B 71.2%
    Winner: Claude Sonnet 4.6Δ 18.7
    GPQA: Claude Sonnet 4.6 scored 89.9%; DeepSeek V4 Flash scored 71.2%. Claude Sonnet 4.6 wins this benchmark.

  3. Terminal-Bench 2.0

    Agentic
    Source ↗
    A 59.1%B 49.1%
    Winner: Claude Sonnet 4.6Δ 10
    Terminal-Bench 2.0: Claude Sonnet 4.6 scored 59.1%; DeepSeek V4 Flash scored 49.1%. Claude Sonnet 4.6 wins this benchmark.

  4. SWE-bench Verified

    Coding
    Source ↗
    A 79.6%B 73.7%
    Winner: Claude Sonnet 4.6Δ 5.9
    SWE-bench Verified: Claude Sonnet 4.6 scored 79.6%; DeepSeek V4 Flash scored 73.7%. Claude Sonnet 4.6 wins this benchmark.

  5. MMLU-Pro

    Knowledge
    Source ↗
    A 79.2%B 83%
    Winner: DeepSeek V4 FlashΔ 3.8
    MMLU-Pro: Claude Sonnet 4.6 scored 79.2%; DeepSeek V4 Flash scored 83%. DeepSeek V4 Flash wins this benchmark.

Operational comparison

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

MetricClaude Sonnet 4.6DeepSeek V4 FlashComparison
Input / output priceUSD per 1M tokensClaude Sonnet 4.6$3 input / $15 outputDeepSeek V4 Flash$0.14 input / $0.28 outputDeepSeek V4 Flash has the lower combined listed price.
Generation speedtokens per secondClaude Sonnet 4.644 tok/sDeepSeek V4 FlashNot availableA complete speed comparison is not available.
First-answer latencyseconds to first tokenClaude Sonnet 4.61.48 sDeepSeek V4 FlashNot availableA complete latency comparison is not available.
Context windowmaximum listed tokensClaude Sonnet 4.6200KDeepSeek V4 Flash1MDeepSeek V4 Flash lists the larger context window.

Benchmark Deep Dive

AgenticClaude Sonnet 4.6 wins
BenchmarkClaude Sonnet 4.6DeepSeek V4 FlashResult
Terminal-Bench 2.0Source 59.1%49.1%Claude Sonnet 4.6 leads
OSWorld-VerifiedSource 72.1%—Not comparable
Claw-EvalSource 67.8%57.8%Claude Sonnet 4.6 leads
CyberGymSource 65.2%—Not comparable
τ²-bench resultsSource 79.5%—Not comparable
Gert LabsSource 62.92%54.35%Claude Sonnet 4.6 leads
OSWorld 2.0Source 8.3%—Not comparable
JobBenchSource 36.9%—Not comparable
MCP AtlasSource —64%Not comparable
ToolathlonSource —40.7%Not comparable
CodingClaude Sonnet 4.6 wins
BenchmarkClaude Sonnet 4.6DeepSeek V4 FlashResult
SWE-bench VerifiedSource 79.6%73.7%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%—Not comparable
FrontierCode 1.1 MainSource 24.3%—Not comparable
SWE-bench ProSource —49.1%Not comparable
SWE MultilingualSource —69.7%Not comparable
Terminal-Bench 2.0Source —49.1%Not comparable
Reasoning
BenchmarkClaude Sonnet 4.6DeepSeek V4 FlashResult
AA-LCRSource 57.7%—Not comparable
CritPtSource 0.9%—Not comparable
MRCR 1MSource —37.5%Not comparable
CorpusQA 1MSource —15.5%Not comparable
KnowledgeClaude Sonnet 4.6 wins
BenchmarkClaude Sonnet 4.6DeepSeek V4 FlashResult
GPQASource 89.9%71.2%Claude Sonnet 4.6 leads
SuperGPQASource 95%—Not comparable
MMLU-ProSource 79.2%83%DeepSeek V4 Flash leads
HLESource 49%8.1%Claude Sonnet 4.6 leads
Artificial Analysis Intelligence IndexSource 35.9%—Not comparable
AA-GPQA DiamondSource 79.9%—Not comparable
AA-HLESource 13.2%—Not comparable
AA-Omniscience IndexSource -2.9%—Not comparable
AA-Omniscience AccuracySource 38.0%—Not comparable
AA-Omniscience Hallucination RateSource 65.9%—Not comparable
SimpleQASource —23.1%Not comparable
Chinese-SimpleQASource —71.5%Not comparable
GPQA-DSource —71.2%Not comparable
MathDeepSeek V4 Flash wins
BenchmarkClaude Sonnet 4.6DeepSeek V4 FlashResult
FrontierMath v2 (Tiers 1-3)Source 32.400%—Not comparable
FrontierMath v2 (Tier 4)Source 8.300%—Not comparable
HMMT Feb 2026Source —40.8%Not comparable
IMOAnswerBenchSource —41.9%Not comparable
ApexSource —1.0%Not comparable
Apex ShortlistSource —9.3%Not comparable
Multimodal
BenchmarkClaude Sonnet 4.6DeepSeek V4 FlashResult
CharXivSource 77.4%—Not comparable
AA-MMMU-ProSource 70.6%—Not comparable
Design Arena WebsiteSource 13141238Claude Sonnet 4.6 leads
Inst. Following
BenchmarkClaude Sonnet 4.6DeepSeek V4 FlashResult
AA-IFBenchSource 41.2%—Not comparable
Frequently Asked Questions (5)

Which is better, Claude Sonnet 4.6 or DeepSeek V4 Flash?

Claude Sonnet 4.6 is ahead on BenchLM's BenchAlign leaderboard, 65.07 to 58.88. The biggest single separator in this matchup is HLE, where the scores are 49% and 8.1%.

Which is better for knowledge tasks, Claude Sonnet 4.6 or DeepSeek V4 Flash?

Claude Sonnet 4.6 has the edge for knowledge tasks in this comparison, averaging 66 versus 38.8. Inside this category, HLE is the benchmark that creates the most daylight between them.

Which is better for coding, Claude Sonnet 4.6 or DeepSeek V4 Flash?

Claude Sonnet 4.6 has the edge for coding in this comparison, averaging 69.1 versus 64.2. Inside this category, SWE-bench Verified is the benchmark that creates the most daylight between them.

Which is better for math, Claude Sonnet 4.6 or DeepSeek V4 Flash?

DeepSeek V4 Flash has the edge for math in this comparison, averaging 40.8 versus 26.4. Claude Sonnet 4.6 stays close enough that the answer can still flip depending on your workload.

Which is better for agentic tasks, Claude Sonnet 4.6 or DeepSeek V4 Flash?

Claude Sonnet 4.6 has the edge for agentic tasks in this comparison, averaging 65.2 versus 49.1. Inside this category, Terminal-Bench 2.0 is the benchmark that creates the most daylight between them.

Related Comparisons

Explore More

Anthropic Compare Pricing Methodology Find Your Best LLM Overall Rankings
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.