Model comparison
DeepSeek V4 Pro (High) vs GPT-5.5 Pro
Head-to-head evidence from 3 shared benchmark results across 3 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: DeepSeek V4 Pro (High) #81 (Estimated); GPT-5.5 Pro #38 (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 Pro share 3 comparable benchmark results. 3 of 8 categories are comparable. 35 results are unique to DeepSeek V4 Pro (High); 4 to GPT-5.5 Pro.
Updated July 23, 2026- Shared results
- 3
- DeepSeek V4 Pro (High) only
- 35
- GPT-5.5 Pro only
- 4
- Comparable categories
- 3 / 8
Pick GPT-5.5 Pro 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 3 shared benchmark results across 3 evidence categories; 3 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 Pro is clearly ahead on the BenchAlign aggregate, 63.69 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 Pro's sharpest advantage is in agentic, where it averages 90.1 against 70.6. The single biggest benchmark swing on the page is HLE, 34.5% to 57.2%. 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 Pro is also the more expensive model on tokens at $30.00 input / $180.00 output per 1M tokens, versus $0.43 input / $0.87 output per 1M tokens for DeepSeek V4 Pro (High). That is roughly 206.9x 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 | DeepSeek V4 Pro (High) | Δ | GPT-5.5 Pro |
|---|---|---|---|
| Math | DeepSeek V4 Pro (High)94.0 | Margin← 45.9 | GPT-5.5 Pro48.1 |
| Agentic | DeepSeek V4 Pro (High)70.6 | Margin→ 19.5 | GPT-5.5 Pro90.1 |
| Knowledge | DeepSeek V4 Pro (High)57.0 | Margin→ 0.2 | GPT-5.5 Pro57.2 |
| Coding | DeepSeek V4 Pro (High)69.8 | MarginNo overlap | GPT-5.5 ProNot measured |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
HLE
KnowledgeA 34.5%B 57.2%Winner: GPT-5.5 ProΔ 22.7HLE: DeepSeek V4 Pro (High) scored 34.5%; GPT-5.5 Pro scored 57.2%. GPT-5.5 Pro wins this benchmark. - Source ↗
BrowseComp
AgenticA 80.4%B 90.1%Winner: GPT-5.5 ProΔ 9.7BrowseComp: DeepSeek V4 Pro (High) scored 80.4%; GPT-5.5 Pro scored 90.1%. GPT-5.5 Pro wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | DeepSeek V4 Pro (High) | GPT-5.5 Pro | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | DeepSeek V4 Pro (High)$0.435 input / $0.87 output | GPT-5.5 Pro$30 input / $180 output | DeepSeek V4 Pro (High) has the lower combined listed price. |
| Generation speedtokens per second | DeepSeek V4 Pro (High)Not available | GPT-5.5 ProNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | DeepSeek V4 Pro (High)Not available | GPT-5.5 ProNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | DeepSeek V4 Pro (High)1M | GPT-5.5 Pro1M | Listed context windows are equal. |
Benchmark Deep Dive
AgenticGPT-5.5 Pro wins9 benchmarks
| Benchmark | DeepSeek V4 Pro (High) | GPT-5.5 Pro | Result |
|---|---|---|---|
| Terminal-Bench 2.0Source | 63.3% | — | Not comparable |
| BrowseCompSource | 80.4% | 90.1% | GPT-5.5 Pro leads |
| HLE w/ toolsSource | 44.7% | — | Not comparable |
| MCP AtlasSource | 74.2% | — | Not comparable |
| ToolathlonSource | 49% | — | Not comparable |
| τ²-bench resultsSource | 94.2% | — | Not comparable |
| GDPval-AASource | 39.9% | — | Not comparable |
| GDPval-AASource | 1299 | — | Not comparable |
| AA Agentic IndexSource | 34.4% | — | Not comparable |
Coding7 benchmarks
| Benchmark | DeepSeek V4 Pro (High) | GPT-5.5 Pro | Result |
|---|---|---|---|
| CodeforcesSource | 2919.0 | — | Not comparable |
| SWE-bench VerifiedSource | 79.4% | — | Not comparable |
| SWE-bench ProSource | 54.4% | — | Not comparable |
| SWE MultilingualSource | 74.1% | — | Not comparable |
| Terminal-Bench 2.0Source | 63.3% | — | Not comparable |
| AA-SciCodeSource | 46.4% | — | Not comparable |
| AA Coding IndexSource | 58.7% | — | Not comparable |
Reasoning4 benchmarks
KnowledgeGPT-5.5 Pro wins13 benchmarks
| Benchmark | DeepSeek V4 Pro (High) | GPT-5.5 Pro | Result |
|---|---|---|---|
| MMLU-ProSource | 87.1% | — | Not comparable |
| SimpleQASource | 46.2% | — | Not comparable |
| Chinese-SimpleQASource | 77.7% | — | Not comparable |
| GPQASource | 89.1% | — | Not comparable |
| GPQA-DSource | 89.1% | — | Not comparable |
| HLESource | 34.5% | 57.2% | GPT-5.5 Pro leads |
| Artificial Analysis Intelligence IndexSource | 43.1% | — | Not comparable |
| AA-GPQA DiamondSource | 90.5% | — | Not comparable |
| AA-HLESource | 33.5% | — | Not comparable |
| AA-Omniscience IndexSource | -9.7% | — | Not comparable |
| AA-Omniscience AccuracySource | 41.8% | — | Not comparable |
| AA-Omniscience Hallucination RateSource | 88.6% | — | Not comparable |
| HLE w/o toolsSource | — | 43.1% | Not comparable |
MathDeepSeek V4 Pro (High) wins7 benchmarks
| Benchmark | DeepSeek V4 Pro (High) | GPT-5.5 Pro | Result |
|---|---|---|---|
| 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 | — | 52.4% | Not comparable |
| FrontierMath v2 (Tiers 1-3)Source | — | 51.000% | Not comparable |
| FrontierMath v2 (Tier 4)Source | — | 39.600% | Not comparable |
Multimodal1 benchmarks
| Benchmark | DeepSeek V4 Pro (High) | GPT-5.5 Pro | Result |
|---|---|---|---|
| Design Arena WebsiteSource | 1264 | — | Not comparable |
Inst. Following1 benchmarks
| Benchmark | DeepSeek V4 Pro (High) | GPT-5.5 Pro | Result |
|---|---|---|---|
| AA-IFBenchSource | 71.3% | — | Not comparable |
Frequently Asked Questions (4)
Which is better, DeepSeek V4 Pro (High) or GPT-5.5 Pro?
GPT-5.5 Pro is ahead on BenchLM's BenchAlign leaderboard, 63.69 to 55.47. The biggest single separator in this matchup is HLE, where the scores are 34.5% and 57.2%.
Which is better for knowledge tasks, DeepSeek V4 Pro (High) or GPT-5.5 Pro?
GPT-5.5 Pro has the edge for knowledge tasks in this comparison, averaging 57.2 versus 57. Inside this category, HLE is the benchmark that creates the most daylight between them.
Which is better for math, DeepSeek V4 Pro (High) or GPT-5.5 Pro?
DeepSeek V4 Pro (High) has the edge for math in this comparison, averaging 94 versus 48.1. GPT-5.5 Pro 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 Pro?
GPT-5.5 Pro has the edge for agentic tasks in this comparison, averaging 90.1 versus 70.6. Inside this category, BrowseComp is the benchmark that creates the most daylight between them.
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