Model comparison
Claude 4.1 Opus Thinking vs GPT-5.3 Codex
Head-to-head evidence from 9 shared benchmark results across 6 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Claude 4.1 Opus Thinking #184 (Supported); GPT-5.3 Codex #26 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude 4.1 Opus Thinking and GPT-5.3 Codex share 9 comparable benchmark results. 0 of 8 categories are comparable. 0 results are unique to Claude 4.1 Opus Thinking; 12 to GPT-5.3 Codex.
Updated July 20, 2026- Shared results
- 9
- Claude 4.1 Opus Thinking only
- 0
- GPT-5.3 Codex only
- 12
- Comparable categories
- 0 / 8
Benchmark data for Claude 4.1 Opus Thinking and GPT-5.3 Codex is coming soon on BenchLM.
Confidence note. This is a partial-evidence comparison with 9 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-5.3 Codex has the larger context window at 400K, compared with 200K for Claude 4.1 Opus 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 4.1 Opus Thinking | Δ | GPT-5.3 Codex |
|---|---|---|---|
| Agentic | Claude 4.1 Opus ThinkingNot measured | MarginNo overlap | GPT-5.3 Codex71.4 |
| Coding | Claude 4.1 Opus ThinkingNot measured | MarginNo overlap | GPT-5.3 Codex67.2 |
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Claude 4.1 Opus Thinking | GPT-5.3 Codex | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude 4.1 Opus ThinkingNot available | GPT-5.3 Codex$1.75 input / $14 output | A complete price comparison is not available. |
| Generation speedtokens per second | Claude 4.1 Opus Thinking29 tok/s | GPT-5.3 Codex79 tok/s | GPT-5.3 Codex has the higher measured throughput. |
| First-answer latencyseconds to first token | Claude 4.1 Opus Thinking15.00 s | GPT-5.3 Codex88.26 s | Claude 4.1 Opus Thinking reaches the first token sooner. |
| Context windowmaximum listed tokens | Claude 4.1 Opus Thinking200K | GPT-5.3 Codex400K | GPT-5.3 Codex lists the larger context window. |
Benchmark Deep Dive
Agentic5 benchmarks
Coding5 benchmarks
Reasoning2 benchmarks
Knowledge6 benchmarks
| Benchmark | Claude 4.1 Opus Thinking | GPT-5.3 Codex | Result |
|---|---|---|---|
| Artificial Analysis Intelligence IndexSource | 33.7% | 44.3% | GPT-5.3 Codex leads |
| AA-GPQA DiamondSource | 80.9% | 91.5% | GPT-5.3 Codex leads |
| AA-HLESource | 11.9% | 39.9% | GPT-5.3 Codex leads |
| AA-Omniscience IndexSource | — | 9.9% | Not comparable |
| AA-Omniscience AccuracySource | — | 51.8% | Not comparable |
| AA-Omniscience Hallucination RateSource | — | 86.9% | Not comparable |
Multimodal2 benchmarks
Inst. Following1 benchmarks
| Benchmark | Claude 4.1 Opus Thinking | GPT-5.3 Codex | Result |
|---|---|---|---|
| AA-IFBenchSource | 55.4% | 75.4% | GPT-5.3 Codex leads |
Frequently Asked Questions (3)
Can I compare Claude 4.1 Opus Thinking and GPT-5.3 Codex 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 4.1 Opus Thinking and GPT-5.3 Codex today?
Claude 4.1 Opus Thinking: Pricing unavailable GPT-5.3 Codex: $1.75 input / $14.00 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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