Model comparison
Claude Opus 4.5 Thinking vs GPT-5.4 nano
Head-to-head evidence from 13 shared benchmark results across 6 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Claude Opus 4.5 Thinking #69 (Estimated); GPT-5.4 nano #25 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude Opus 4.5 Thinking and GPT-5.4 nano share 13 comparable benchmark results. 0 of 8 categories are comparable. 3 results are unique to Claude Opus 4.5 Thinking; 16 to GPT-5.4 nano.
Updated July 23, 2026- Shared results
- 13
- Claude Opus 4.5 Thinking only
- 3
- GPT-5.4 nano only
- 16
- Comparable categories
- 0 / 8
Benchmark data for Claude Opus 4.5 Thinking and GPT-5.4 nano is coming soon on BenchLM.
Confidence note. This is a partial-evidence comparison with 13 shared benchmark results across 6 evidence categories; 0 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
BenchLM has partial data for these models, but not enough overlapping benchmark coverage to produce a fair score-level comparison yet.
GPT-5.4 nano has the larger context window at 400K, compared with 200K for Claude Opus 4.5 Thinking.
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 | Claude Opus 4.5 Thinking | Δ | GPT-5.4 nano |
|---|---|---|---|
| Agentic | Claude Opus 4.5 ThinkingNot measured | MarginNo overlap | GPT-5.4 nano42.9 |
| Knowledge | Claude Opus 4.5 ThinkingNot measured | MarginNo overlap | GPT-5.4 nano43.8 |
| Math | Claude Opus 4.5 ThinkingNot measured | MarginNo overlap | GPT-5.4 nano21.0 |
| Multimodal | Claude Opus 4.5 ThinkingNot measured | MarginNo overlap | GPT-5.4 nano66.1 |
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Claude Opus 4.5 Thinking | GPT-5.4 nano | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude Opus 4.5 ThinkingNot available | GPT-5.4 nano$0.2 input / $1.25 output | A complete price comparison is not available. |
| Generation speedtokens per second | Claude Opus 4.5 ThinkingNot available | GPT-5.4 nano191 tok/s | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude Opus 4.5 ThinkingNot available | GPT-5.4 nano3.64 s | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude Opus 4.5 Thinking200K | GPT-5.4 nano400K | GPT-5.4 nano lists the larger context window. |
Benchmark Deep Dive
Agentic9 benchmarks
| Benchmark | Claude Opus 4.5 Thinking | GPT-5.4 nano | Result |
|---|---|---|---|
| τ²-bench resultsSource | 89.5% | 76% | Claude Opus 4.5 Thinking leads |
| Terminal-Bench 2.0Source | — | 46.3% | Not comparable |
| OSWorld-VerifiedSource | — | 39% | Not comparable |
| MCP AtlasSource | — | 56.1% | Not comparable |
| ToolathlonSource | — | 35.5% | Not comparable |
| AA Agentic IndexSource | — | 27.5% | Not comparable |
| APEX-Agents-AASource | — | 24.9% | Not comparable |
| GDPval-AASource | — | 30.0% | Not comparable |
| GDPval-AASource | — | 1100 | Not comparable |
Coding3 benchmarks
Reasoning2 benchmarks
Knowledge10 benchmarks
| Benchmark | Claude Opus 4.5 Thinking | GPT-5.4 nano | Result |
|---|---|---|---|
| Artificial Analysis Intelligence IndexSource | 40.8% | 38.2% | Claude Opus 4.5 Thinking leads |
| AA-GPQA DiamondSource | 86.6% | 81.7% | Claude Opus 4.5 Thinking leads |
| AA-HLESource | 28.4% | 26.5% | Claude Opus 4.5 Thinking leads |
| AA-Omniscience IndexSource | 13.3% | -29.5% | Claude Opus 4.5 Thinking leads |
| AA-Omniscience AccuracySource | 45.7% | 25.4% | Claude Opus 4.5 Thinking leads |
| AA-Omniscience Hallucination RateSource | 59.8% | 73.6% | Claude Opus 4.5 Thinking leads |
| AA MMLU-ProSource | 89.5% | — | Not comparable |
| GPQASource | — | 82.8% | Not comparable |
| HLESource | — | 37.7% | Not comparable |
| HLE w/o toolsSource | — | 24.3% | Not comparable |
Math2 benchmarks
Multilingual1 benchmarks
| Benchmark | Claude Opus 4.5 Thinking | GPT-5.4 nano | Result |
|---|---|---|---|
| AA Global-MMLU-LiteSource | 91.3% | — | Not comparable |
Multimodal4 benchmarks
Inst. Following1 benchmarks
| Benchmark | Claude Opus 4.5 Thinking | GPT-5.4 nano | Result |
|---|---|---|---|
| AA-IFBenchSource | 58.0% | 75.9% | GPT-5.4 nano leads |
Frequently Asked Questions (3)
Can I compare Claude Opus 4.5 Thinking and GPT-5.4 nano on BenchLM yet?
Not fully yet. BenchLM is tracking both models, but the sourced benchmark breakdown for this comparison is still coming soon.
Why does this comparison show “coming soon”?
BenchLM only shows category winners and benchmark-level calls when we have sourced results that can be compared fairly. For these models, the public benchmark coverage is not complete enough yet.
What data is available for Claude Opus 4.5 Thinking and GPT-5.4 nano today?
GPT-5.4 nano: $0.20 input / $1.25 output per 1M tokens Both model pages still include creator, context window, reasoning mode, and other metadata while benchmark coverage fills in.
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