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Model comparison

DeepSeek V4 Pro (High) vs GPT-5.5

Data verified

Head-to-head evidence from 25 shared benchmark results across 6 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.

55.47/100
Margin
18.0pts
winning →
OpenAI
73.51/100
2 category wins2 category wins

Public leaderboard positions: DeepSeek V4 Pro (High) #81 (Estimated); GPT-5.5 #9 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.

Evidence parity. DeepSeek V4 Pro (High) and GPT-5.5 share 25 comparable benchmark results. 4 of 8 categories are comparable. 13 results are unique to DeepSeek V4 Pro (High); 32 to GPT-5.5.

Updated July 23, 2026
Shared results
25
DeepSeek V4 Pro (High) only
13
GPT-5.5 only
32
Comparable categories
4 / 8

Pick GPT-5.5 if you want the stronger benchmark profile. DeepSeek V4 Pro (High) 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 25 shared benchmark results across 6 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

GPT-5.5 is clearly ahead on the BenchAlign aggregate, 73.51 to 55.47. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

GPT-5.5's sharpest advantage is in agentic, where it averages 81.6 against 70.6. The single biggest benchmark swing on the page is Terminal-Bench 2.0, 63.3% to 82%. DeepSeek V4 Pro (High) does hit back in mathematics, so the answer changes if that is the part of the workload you care about most.

GPT-5.5 is also the more expensive model on tokens at $5.00 input / $30.00 output per 1M tokens, versus $0.43 input / $0.87 output per 1M tokens for DeepSeek V4 Pro (High). That is roughly 34.5x on output cost alone.

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 DeepSeek V4 Pro (High) and GPT-5.5
CategoryDeepSeek V4 Pro (High)ΔGPT-5.5
MathDeepSeek V4 Pro (High)94.0Margin 46.4GPT-5.547.6
CodingDeepSeek V4 Pro (High)69.8Margin 11.2GPT-5.558.6
AgenticDeepSeek V4 Pro (High)70.6Margin 11.0GPT-5.581.6
KnowledgeDeepSeek V4 Pro (High)57.0Margin 0.8GPT-5.557.8
ReasoningDeepSeek V4 Pro (High)Not measuredMarginNo overlapGPT-5.585.0
MultimodalDeepSeek V4 Pro (High)Not measuredMarginNo overlapGPT-5.570.4

Decisive benchmark drivers

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

More
A · DeepSeek V4 Pro (High)B · GPT-5.5
  1. Terminal-Bench 2.0

    Agentic
    Source ↗
    A 63.3%B 82%
    Winner: GPT-5.5Δ 18.7
    Terminal-Bench 2.0: DeepSeek V4 Pro (High) scored 63.3%; GPT-5.5 scored 82%. GPT-5.5 wins this benchmark.
  2. HLE

    Knowledge
    Source ↗
    A 34.5%B 52.2%
    Winner: GPT-5.5Δ 17.7
    HLE: DeepSeek V4 Pro (High) scored 34.5%; GPT-5.5 scored 52.2%. GPT-5.5 wins this benchmark.
  3. GPQA

    Knowledge
    Source ↗
    A 89.1%B 93.6%
    Winner: GPT-5.5Δ 4.5
    GPQA: DeepSeek V4 Pro (High) scored 89.1%; GPT-5.5 scored 93.6%. GPT-5.5 wins this benchmark.
  4. SWE-bench Pro

    Coding
    Source ↗
    A 54.4%B 58.6%
    Winner: GPT-5.5Δ 4.2
    SWE-bench Pro: DeepSeek V4 Pro (High) scored 54.4%; GPT-5.5 scored 58.6%. GPT-5.5 wins this benchmark.
  5. BrowseComp

    Agentic
    Source ↗
    A 80.4%B 84.4%
    Winner: GPT-5.5Δ 4
    BrowseComp: DeepSeek V4 Pro (High) scored 80.4%; GPT-5.5 scored 84.4%. GPT-5.5 wins this benchmark.

Operational comparison

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

MetricDeepSeek V4 Pro (High)GPT-5.5Comparison
Input / output priceUSD per 1M tokensDeepSeek V4 Pro (High)$0.435 input / $0.87 outputGPT-5.5$5 input / $30 outputDeepSeek V4 Pro (High) has the lower combined listed price.
Generation speedtokens per secondDeepSeek V4 Pro (High)Not availableGPT-5.5Not availableA complete speed comparison is not available.
First-answer latencyseconds to first tokenDeepSeek V4 Pro (High)Not availableGPT-5.5Not availableA complete latency comparison is not available.
Context windowmaximum listed tokensDeepSeek V4 Pro (High)1MGPT-5.51MListed context windows are equal.

Benchmark Deep Dive

AgenticGPT-5.5 wins
BenchmarkDeepSeek V4 Pro (High)GPT-5.5Result
Terminal-Bench 2.0Source 63.3%82%GPT-5.5 leads
BrowseCompSource 80.4%84.4%GPT-5.5 leads
HLE w/ toolsSource 44.7%Not comparable
MCP AtlasSource 74.2%75.3%GPT-5.5 leads
ToolathlonSource 49%55.6%GPT-5.5 leads
τ²-bench resultsSource 94.2%93.9%DeepSeek V4 Pro (High) leads
GDPval-AASource 39.9%49.5%GPT-5.5 leads
GDPval-AASource 12991490GPT-5.5 leads
AA Agentic IndexSource 34.4%44.9%GPT-5.5 leads
CyberGymSource 81.8%Not comparable
OSWorld-VerifiedSource 78.7%Not comparable
APEX-Agents-AASource 37.7%Not comparable
Gert LabsSource 72.93%Not comparable
ResearchClawBenchSource 17.0%Not comparable
OSWorld 2.0Source 13.0%Not comparable
JobBenchSource 42.7%Not comparable
ExploitGymSource 13.4%Not comparable
AA BriefcaseSource 1154Not comparable
AA AutomationBenchSource 42.1%Not comparable
AA EnterpriseOps-GymSource 46.6%Not comparable
AA Harvey LABSource 86.3%Not comparable
AA ITBenchSource 45.8%Not comparable
AA Tau3 BankingSource 31.3%Not comparable
terminalBenchHardSource 60.6%Not comparable
aaTerminalBench21Source 84.3%Not comparable
CodingDeepSeek V4 Pro (High) wins
BenchmarkDeepSeek V4 Pro (High)GPT-5.5Result
CodeforcesSource 2919.0Not comparable
SWE-bench VerifiedSource 79.4%Not comparable
SWE-bench ProSource 54.4%58.6%GPT-5.5 leads
SWE MultilingualSource 74.1%Not comparable
Terminal-Bench 2.0Source 63.3%82.0%GPT-5.5 leads
AA-SciCodeSource 46.4%56.1%GPT-5.5 leads
AA Coding IndexSource 58.7%74.9%GPT-5.5 leads
Vibe Code BenchSource 69.85%Not comparable
React Native EvalsSource 84.7%Not comparable
cursorBench31Source 59.2%Not comparable
cursorBench32Source 58.4%Not comparable
FrontierCode 1.1 MainSource 43.0%Not comparable
Reasoning
BenchmarkDeepSeek V4 Pro (High)GPT-5.5Result
MRCR 1MSource 83.3%Not comparable
CorpusQA 1MSource 56.5%Not comparable
AA-LCRSource 65.0%74.3%GPT-5.5 leads
CritPtSource 10.0%27.1%GPT-5.5 leads
MRCR v2 64K-128KSource 83.1%Not comparable
MRCR v2 128K-256KSource 87.5%Not comparable
ARC-AGI-2Source 85%Not comparable
KnowledgeGPT-5.5 wins
BenchmarkDeepSeek V4 Pro (High)GPT-5.5Result
MMLU-ProSource 87.1%Not comparable
SimpleQASource 46.2%Not comparable
Chinese-SimpleQASource 77.7%Not comparable
GPQASource 89.1%93.6%GPT-5.5 leads
GPQA-DSource 89.1%93.6%GPT-5.5 leads
HLESource 34.5%52.2%GPT-5.5 leads
Artificial Analysis Intelligence IndexSource 43.1%54.8%GPT-5.5 leads
AA-GPQA DiamondSource 90.5%93.5%GPT-5.5 leads
AA-HLESource 33.5%44.3%GPT-5.5 leads
AA-Omniscience IndexSource -9.7%20.1%GPT-5.5 leads
AA-Omniscience AccuracySource 41.8%56.9%GPT-5.5 leads
AA-Omniscience Hallucination RateSource 88.6%85.5%GPT-5.5 leads
HLE w/o toolsSource 41.4%Not comparable
MathDeepSeek V4 Pro (High) wins
BenchmarkDeepSeek V4 Pro (High)GPT-5.5Result
HMMT Feb 2026Source 94.0%Not comparable
IMOAnswerBenchSource 88.0%Not comparable
ApexSource 27.4%Not comparable
Apex ShortlistSource 85.5%Not comparable
FrontierMath (legacy)Source 51.7%Not comparable
FrontierMath v2 (Tiers 1-3)Source 51.700%Not comparable
FrontierMath v2 (Tier 4)Source 35.400%Not comparable
Multimodal
BenchmarkDeepSeek V4 Pro (High)GPT-5.5Result
Design Arena WebsiteSource 12641282GPT-5.5 leads
MMMU-ProSource 81.2%Not comparable
MMMU-Pro w/ PythonSource 83.2%Not comparable
OfficeQA ProSource 54.1%Not comparable
AA-MMMU-ProSource 79.9%Not comparable
Inst. Following
BenchmarkDeepSeek V4 Pro (High)GPT-5.5Result
AA-IFBenchSource 71.3%75.9%GPT-5.5 leads
Frequently Asked Questions (5)

Which is better, DeepSeek V4 Pro (High) or GPT-5.5?

GPT-5.5 is ahead on BenchLM's BenchAlign leaderboard, 73.51 to 55.47. The biggest single separator in this matchup is Terminal-Bench 2.0, where the scores are 63.3% and 82%.

Which is better for knowledge tasks, DeepSeek V4 Pro (High) or GPT-5.5?

GPT-5.5 has the edge for knowledge tasks in this comparison, averaging 57.8 versus 57. Inside this category, AA-Omniscience Index is the benchmark that creates the most daylight between them.

Which is better for coding, DeepSeek V4 Pro (High) or GPT-5.5?

DeepSeek V4 Pro (High) has the edge for coding in this comparison, averaging 69.8 versus 58.6. Inside this category, Terminal-Bench 2.0 is the benchmark that creates the most daylight between them.

Which is better for math, DeepSeek V4 Pro (High) or GPT-5.5?

DeepSeek V4 Pro (High) has the edge for math in this comparison, averaging 94 versus 47.6. GPT-5.5 stays close enough that the answer can still flip depending on your workload.

Which is better for agentic tasks, DeepSeek V4 Pro (High) or GPT-5.5?

GPT-5.5 has the edge for agentic tasks in this comparison, averaging 81.6 versus 70.6. Inside this category, GDPval-AA is the benchmark that creates the most daylight between them.

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Last updated: July 23, 2026

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